diff --git a/swad_MFU.c b/swad_MFU.c
index 051c9ecf..dc843fb2 100644
--- a/swad_MFU.c
+++ b/swad_MFU.c
@@ -220,7 +220,7 @@ void MFU_WriteBigMFUActions (struct MFU_ListMFUActions *ListMFUActions)
    /***** Start box *****/
    Box_StartBox (NULL,Txt_My_frequent_actions,NULL,
                  Hlp_ANALYTICS_Frequent,Box_NOT_CLOSABLE);
-   fprintf (Gbl.F.Out,"<div id=\"MFU_actions_big\">");
+   HTM_DIV_Begin ("id=\"MFU_actions_big\"");
 
    /***** Write list of frequently used actions *****/
    fprintf (Gbl.F.Out,"<ul class=\"LIST_LEFT\">");
@@ -277,7 +277,7 @@ void MFU_WriteSmallMFUActions (struct MFU_ListMFUActions *ListMFUActions)
    char TabMenuStr[MFU_MAX_BYTES_TAB + 6 + MFU_MAX_BYTES_MENU + 1];
 
    /***** Start div and link *****/
-   fprintf (Gbl.F.Out,"<div id=\"MFU_actions\">");
+   HTM_DIV_Begin ("id=\"MFU_actions\"");
    Frm_StartForm (ActMFUAct);
    Frm_LinkFormSubmit (Txt_My_frequent_actions,NULL,NULL);
    fprintf (Gbl.F.Out," %s"
diff --git a/swad_QR.c b/swad_QR.c
index 67a126c0..7d4b2959 100644
--- a/swad_QR.c
+++ b/swad_QR.c
@@ -105,8 +105,8 @@ void QR_PrintQRCode (void)
 
 void QR_ImageQRCode (const char *QRString)
   {
-   fprintf (Gbl.F.Out,"<div class=\"CM\" style=\"margin:0 auto; width:%upx;\">",
-	    QR_CODE_SIZE);
+   HTM_DIV_Begin ("class=\"CM\" style=\"margin:0 auto; width:%upx;\"",
+		  QR_CODE_SIZE);
    fprintf (Gbl.F.Out,"<img src=\"https://chart.googleapis.com/chart?cht=qr&amp;chs=%ux%u&amp;chl=%s\""
                       " alt=\"%s\" title=\"%s\""
                       " style=\"width:%upx; height:%upx;"
@@ -149,7 +149,7 @@ void QR_ExamAnnnouncement (void)
    extern const char *Txt_Link_to_announcement_of_exam;
 
    /***** Show QR code with direct link to the exam announcement *****/
-   fprintf (Gbl.F.Out,"<div class=\"CM\">");
+   HTM_DIV_Begin ("class=\"CM\"");
    fprintf (Gbl.F.Out,"<img src=\"https://chart.googleapis.com/chart?cht=qr&amp;chs=%ux%u&amp;chl=%s/?crs=%ld%%26act=%ld\""
                       " alt=\"%s\" title=\"%s\""
                       " style=\"width:250px; height:250px;\" />",
diff --git a/swad_alert.c b/swad_alert.c
index 35cdfd22..7e293b06 100644
--- a/swad_alert.c
+++ b/swad_alert.c
@@ -432,11 +432,11 @@ static void Ale_ShowFixAlertAndButton1 (Ale_AlertType_t AlertType,const char *Tx
      }
 
    /***** Write message *****/
-   fprintf (Gbl.F.Out,"<div class=\"ALERT_TXT\"");
-   if (AlertType != Ale_NONE)
-      fprintf (Gbl.F.Out," style=\"background-image:url('%s/%s');\"",
-	       Cfg_URL_ICON_PUBLIC,Ale_AlertIcons[AlertType]);
-   fprintf (Gbl.F.Out,">");
+   if (AlertType == Ale_NONE)
+      HTM_DIV_Begin ("class=\"ALERT_TXT\"");
+   else
+      HTM_DIV_Begin ("class=\"ALERT_TXT\" style=\"background-image:url('%s/%s');\"",
+	             Cfg_URL_ICON_PUBLIC,Ale_AlertIcons[AlertType]);
    fprintf (Gbl.F.Out,"%s",Txt);
    HTM_DIV_End ();
   }
diff --git a/swad_attendance.c b/swad_attendance.c
index b49d0046..254adb63 100644
--- a/swad_attendance.c
+++ b/swad_attendance.c
@@ -3420,17 +3420,16 @@ static void Att_PutCheckOrCross (bool Present)
    extern const char *Txt_Present;
    extern const char *Txt_Absent;
 
-   fprintf (Gbl.F.Out,"<div class=\"");
-
    if (Present)
-      fprintf (Gbl.F.Out,"ATT_CHECK\" title=\"%s\">"
-			 "&check;",
-	       Txt_Present);
+     {
+      HTM_DIV_Begin ("class=\"ATT_CHECK\" title=\"%s\"",Txt_Present);
+      fprintf (Gbl.F.Out,"&check;");
+     }
    else
-      fprintf (Gbl.F.Out,"ATT_CROSS\" title=\"%s\">"
-			 "&cross;",
-	       Txt_Absent);
-
+     {
+      HTM_DIV_Begin ("class=\"ATT_CROSS\" title=\"%s\"",Txt_Absent);
+      fprintf (Gbl.F.Out,"&cross;");
+     }
    HTM_DIV_End ();
   }
 
diff --git a/swad_box.c b/swad_box.c
index 94973f29..0306f7c7 100644
--- a/swad_box.c
+++ b/swad_box.c
@@ -139,20 +139,21 @@ static void Box_StartBoxInternal (const char *Width,const char *Title,
       Gbl.Box.Ids[Gbl.Box.Nested] = NULL;
 
    /***** Start box container *****/
-   fprintf (Gbl.F.Out,"<div class=\"FRAME_CONTAINER\"");
    if (Closable == Box_CLOSABLE)
      {
       /* Create unique id for alert */
       Frm_SetUniqueId (Gbl.Box.Ids[Gbl.Box.Nested]);
-      fprintf (Gbl.F.Out," id=\"%s\"",Gbl.Box.Ids[Gbl.Box.Nested]);
+
+      HTM_DIV_Begin ("class=\"FRAME_CONTAINER\" id=\"%s\"",Gbl.Box.Ids[Gbl.Box.Nested]);
      }
-   fprintf (Gbl.F.Out,">");
+   else
+      HTM_DIV_Begin ("class=\"FRAME_CONTAINER\"");
 
    /***** Start box *****/
-   fprintf (Gbl.F.Out,"<div class=\"%s\"",ClassFrame);
    if (Width)
-       fprintf (Gbl.F.Out," style=\"width:%s;\"",Width);
-   fprintf (Gbl.F.Out,">");
+      HTM_DIV_Begin ("class=\"%s\" style=\"width:%s;\"",ClassFrame,Width);
+   else
+      HTM_DIV_Begin ("class=\"%s\"",ClassFrame);
 
    /***** Row for left and right icons *****/
    HTM_DIV_Begin ("class=\"FRAME_ICO\"");
diff --git a/swad_changelog.h b/swad_changelog.h
index 728f68bc..4ae99239 100644
--- a/swad_changelog.h
+++ b/swad_changelog.h
@@ -487,7 +487,7 @@ enscript -2 --landscape --color --file-align=2 --highlight --line-numbers -o - *
 En OpenSWAD:
 ps2pdf source.ps destination.pdf
 */
-#define Log_PLATFORM_VERSION	"SWAD 19.42.3 (2019-10-23)"
+#define Log_PLATFORM_VERSION	"SWAD 19.42.4 (2019-10-23)"
 #define CSS_FILE		"swad19.41.3.css"
 #define JS_FILE			"swad19.39.js"
 /*
@@ -495,6 +495,7 @@ ps2pdf source.ps destination.pdf
 // TODO: Hacer un nuevo rol en los TFG: tutor externo (profesor de áreas no vinculadas con el centro, profesionales de empresas, etc.)
 // TODO: Change icon to upload file in timeline to photo-video.svg
 
+	Version 19.42.4:  Oct 23, 2019	Code refactoring in HTML divs. (246016 lines)
 	Version 19.42.3:  Oct 23, 2019	Code refactoring in HTML divs. (246052 lines)
 	Version 19.42.2:  Oct 23, 2019	Code refactoring in HTML divs. (246025 lines)
 	Version 19.42.1:  Oct 23, 2019	Code refactoring in HTML divs. (246088 lines)
diff --git a/swad_file_browser.c b/swad_file_browser.c
index c3a41aa7..3f8b8672 100644
--- a/swad_file_browser.c
+++ b/swad_file_browser.c
@@ -3372,7 +3372,7 @@ static void Brw_ShowDataOwnerAsgWrk (struct UsrData *UsrDat)
    /***** Begin form to send a message to this user *****/
    HTM_TD_Begin ("class=\"LT\"");
 
-   fprintf (Gbl.F.Out,"<div class=\"OWNER_WORKS_DATA AUTHOR_TXT\">");
+   HTM_DIV_Begin ("class=\"OWNER_WORKS_DATA AUTHOR_TXT\"");
 
    switch (UsrDat->Roles.InCurrentCrs.Role)
      {
@@ -3768,7 +3768,7 @@ static void Brw_WriteTopBeforeShowingFileBrowser (void)
    Brw_UpdateLastAccess ();
 
    /***** Write contextual links *****/
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 
    /* Put checkbox to show the full tree */
    Brw_PutCheckboxFullTree ();
@@ -4069,7 +4069,7 @@ static void Brw_WriteSubtitleOfFileBrowser (void)
      }
    if (Subtitle[0])
      {
-      fprintf (Gbl.F.Out,"<div class=\"BROWSER_SUBTITLE\">");
+      HTM_DIV_Begin ("class=\"BROWSER_SUBTITLE\"");
       fprintf (Gbl.F.Out,"%s",Subtitle);
       HTM_DIV_End ();
      }
@@ -4104,7 +4104,7 @@ static void Brw_ShowAndStoreSizeOfFileTree (void)
    extern const char *Txt_of_PART_OF_A_TOTAL;
    char FileSizeStr[Fil_MAX_BYTES_FILE_SIZE_STRING + 1];
 
-   fprintf (Gbl.F.Out,"<div class=\"DAT CM\">");
+   HTM_DIV_Begin ("class=\"DAT CM\"");
 
    if (Brw_FileBrowserIsEditable[Gbl.FileBrowser.Type])
      {
@@ -5899,11 +5899,10 @@ static void Brw_PutIconToExpandFolder (const char *FileBrowserId,const char *Row
    char JavaScriptFuncToExpandFolder[256 + Brw_MAX_ROW_ID];
 
    /***** Start container *****/
-   fprintf (Gbl.F.Out,"<div id=\"expand_%s_%s\"",
-	    FileBrowserId,RowId);
    if (Hidden)
-      fprintf (Gbl.F.Out," style=\"display:none;\"");
-   fprintf (Gbl.F.Out,">");
+      HTM_DIV_Begin ("id=\"expand_%s_%s\" style=\"display:none;\"",FileBrowserId,RowId);
+   else
+      HTM_DIV_Begin ("id=\"expand_%s_%s\"",FileBrowserId,RowId);
 
    /***** Form and icon *****/
    snprintf (JavaScriptFuncToExpandFolder,sizeof (JavaScriptFuncToExpandFolder),
@@ -5931,11 +5930,10 @@ static void Brw_PutIconToContractFolder (const char *FileBrowserId,const char *R
    char JavaScriptFuncToContractFolder[256 + Brw_MAX_ROW_ID];
 
    /***** Start container *****/
-   fprintf (Gbl.F.Out,"<div id=\"contract_%s_%s\"",
-	    FileBrowserId,RowId);
    if (Hidden)
-      fprintf (Gbl.F.Out," style=\"display:none;\"");
-   fprintf (Gbl.F.Out,">");
+      HTM_DIV_Begin ("id=\"contract_%s_%s\" style=\"display:none;\"",FileBrowserId,RowId);
+   else
+      HTM_DIV_Begin ("id=\"contract_%s_%s\"",FileBrowserId,RowId);
 
    /***** Form and icon *****/
    snprintf (JavaScriptFuncToContractFolder,sizeof (JavaScriptFuncToContractFolder),
@@ -6076,13 +6074,16 @@ static void Brw_PutIconFolderWithoutPlus (const char *FileBrowserId,const char *
    extern const char *Txt_Folder;
 
    /***** Start container *****/
-   fprintf (Gbl.F.Out,"<div id=\"folder_%s_%s_%s\"",
-	    Open ? "open" :
-		   "closed",
-	    FileBrowserId,RowId);
    if (Hidden)
-      fprintf (Gbl.F.Out," style=\"display:none;\"");
-   fprintf (Gbl.F.Out,">");
+      HTM_DIV_Begin ("id=\"folder_%s_%s_%s\" style=\"display:none;\"",
+		     Open ? "open" :
+			    "closed",
+		     FileBrowserId,RowId);
+   else
+      HTM_DIV_Begin ("id=\"folder_%s_%s_%s\"",
+		     Open ? "open" :
+			    "closed",
+		     FileBrowserId,RowId);
 
    /***** Icon *****/
    fprintf (Gbl.F.Out,"<img src=\"%s/%s\""
@@ -6106,13 +6107,16 @@ static void Brw_PutIconFolderWithPlus (const char *FileBrowserId,const char *Row
 				       bool Open,bool Hidden)
   {
    /***** Start container *****/
-   fprintf (Gbl.F.Out,"<div id=\"folder_%s_%s_%s\"",
-	    Open ? "open" :
-		   "closed",
-	    FileBrowserId,RowId);
    if (Hidden)
-      fprintf (Gbl.F.Out," style=\"display:none;\"");
-   fprintf (Gbl.F.Out,">");
+      HTM_DIV_Begin ("id=\"folder_%s_%s_%s\" style=\"display:none;\"",
+		     Open ? "open" :
+			    "closed",
+		     FileBrowserId,RowId);
+   else
+      HTM_DIV_Begin ("id=\"folder_%s_%s_%s\"",
+		     Open ? "open" :
+			    "closed",
+		     FileBrowserId,RowId);
 
    /***** Form and icon *****/
    Ico_PutContextualIconToCreateInFolder (Brw_ActFormCreate[Gbl.FileBrowser.Type],
@@ -6253,7 +6257,7 @@ static void Brw_WriteFileName (unsigned Level,bool IsPublic)
 	 HTM_TD_Begin ("class=\"%s LM\" style=\"width:99%%;\"",
 		       Gbl.FileBrowser.TxtStyle);
 
-      fprintf (Gbl.F.Out,"<div class=\"FILENAME\">");
+      HTM_DIV_Begin ("class=\"FILENAME\"");
 
       /***** Form to rename folder *****/
       if (Gbl.FileBrowser.ICanEditFileOrFolder)	// Can I rename this folder?
@@ -6306,7 +6310,7 @@ static void Brw_WriteFileName (unsigned Level,bool IsPublic)
 		       Gbl.FileBrowser.TxtStyle);
 
       fprintf (Gbl.F.Out,"&nbsp;");
-      fprintf (Gbl.F.Out,"<div class=\"FILENAME\">");
+      HTM_DIV_Begin ("class=\"FILENAME\"");
 
       Frm_StartForm (Brw_ActDowFile[Gbl.FileBrowser.Type]);
       Brw_PutImplicitParamsFileBrowser ();
@@ -8380,7 +8384,7 @@ static void Brw_PutFormToUploadFilesUsingDropzone (const char *FileNameToShow)
    extern const char *Txt_Done;
 
    /***** Start box *****/
-   fprintf (Gbl.F.Out,"<div id=\"dropzone-upload\">");
+   HTM_DIV_Begin ("id=\"dropzone-upload\"");
    Box_StartBox ("95%",Txt_Upload_files,NULL,
                  NULL,Box_NOT_CLOSABLE);
 
@@ -8404,7 +8408,7 @@ static void Brw_PutFormToUploadFilesUsingDropzone (const char *FileNameToShow)
    Par_PutHiddenParamString ("ses",Gbl.Session.Id);
    Brw_PutImplicitParamsFileBrowser ();
 
-   fprintf (Gbl.F.Out,"<div class=\"dz-message\">");
+   HTM_DIV_Begin ("class=\"dz-message\"");
    fprintf (Gbl.F.Out,"<span class=\"DAT_LIGHT\">%s</span>",
             Txt_Select_one_or_more_files_from_your_computer_or_drag_and_drop_here);
    HTM_DIV_End ();
@@ -8438,7 +8442,7 @@ static void Brw_PutFormToUploadOneFileClassic (const char *FileNameToShow)
    extern const char *Txt_or_you_can_upload_a_new_file_to_the_folder_X;
 
    /***** Start box *****/
-   fprintf (Gbl.F.Out,"<div id=\"classic-upload\" style=\"display:none;\">");
+   HTM_DIV_Begin ("id=\"classic-upload\" style=\"display:none;\"");
    Box_StartBox (NULL,Txt_Upload_file,NULL,
                  NULL,Box_NOT_CLOSABLE);
 
diff --git a/swad_follow.c b/swad_follow.c
index d17b057d..f94be6f6 100644
--- a/swad_follow.c
+++ b/swad_follow.c
@@ -135,7 +135,7 @@ void Fol_SuggestUsrsToFollowMainZone (void)
    struct UsrData UsrDat;
 
    /***** Put links to request my public profile and another user's profile *****/
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
    Prf_PutLinkMyPublicProfile ();
    Prf_PutLinkRequestAnotherUserProfile ();
    HTM_DIV_End ();
@@ -208,7 +208,7 @@ void Fol_SuggestUsrsToFollowMainZoneOnRightColumn (void)
                                        &mysql_res)))
      {
       /***** Start container *****/
-      fprintf (Gbl.F.Out,"<div class=\"CONNECTED\">");
+      HTM_DIV_Begin ("class=\"CONNECTED\"");
 
       /***** Title with link to suggest more users to follow *****/
       Frm_StartForm (ActSeeSocPrf);
@@ -518,11 +518,11 @@ void Fol_ShowFollowingAndFollowers (const struct UsrData *UsrDat,
    Lay_StartSection (Fol_FOLLOW_SECTION_ID);
 
    /***** Followed users *****/
-   fprintf (Gbl.F.Out,"<div id=\"following_side\">");
-   fprintf (Gbl.F.Out,"<div class=\"FOLLOW_SIDE\">");
+   HTM_DIV_Begin ("id=\"following_side\"");
+   HTM_DIV_Begin ("class=\"FOLLOW_SIDE\"");
 
    /* User follows me? */
-   fprintf (Gbl.F.Out,"<div id=\"follows_me\" class=\"DAT_LIGHT\">");
+   HTM_DIV_Begin ("id=\"follows_me\" class=\"DAT_LIGHT\"");
    if (UsrFollowsMe)
       fprintf (Gbl.F.Out,"%s",Txt_FOLLOWS_YOU);
    HTM_DIV_End ();
@@ -537,8 +537,8 @@ void Fol_ShowFollowingAndFollowers (const struct UsrData *UsrDat,
    HTM_DIV_End ();
 
    /***** Followers *****/
-   fprintf (Gbl.F.Out,"<div id=\"followers_side\">");
-   fprintf (Gbl.F.Out,"<div class=\"FOLLOW_SIDE\">");
+   HTM_DIV_Begin ("id=\"followers_side\"");
+   HTM_DIV_Begin ("class=\"FOLLOW_SIDE\"");
 
    /* Number of followers */
    Fol_ShowNumberOfFollowingOrFollowers (UsrDat,
@@ -546,7 +546,7 @@ void Fol_ShowFollowingAndFollowers (const struct UsrData *UsrDat,
                                          ActSeeFlr,Txt_Followers);
 
    /* I follow user? */
-   fprintf (Gbl.F.Out,"<div id=\"follow_usr\">");
+   HTM_DIV_Begin ("id=\"follow_usr\"");
    if (Gbl.Usrs.Me.Logged &&	// Logged
        !ItsMe)			// Not me!
      {
@@ -555,8 +555,7 @@ void Fol_ShowFollowingAndFollowers (const struct UsrData *UsrDat,
 	 Frm_StartForm (ActUnfUsr);
 	 Usr_PutParamUsrCodEncrypted (UsrDat->EncryptedUsrCod);
 	 Frm_LinkFormSubmit (Txt_Following_unfollow,"REC_DAT_BOLD",NULL);
-	 fprintf (Gbl.F.Out,"<div class=\"ICO_HIGHLIGHT\""
-			    " style=\"display:inline;\" >");
+	 HTM_DIV_Begin ("class=\"ICO_HIGHLIGHT\" style=\"display:inline;\"");
 	 fprintf (Gbl.F.Out,"<img src=\"%s/user-check.svg\""
 			    " alt=\"%s\" title=\"%s\""
 			    " class=\"ICO40x40\" />",
@@ -571,8 +570,7 @@ void Fol_ShowFollowingAndFollowers (const struct UsrData *UsrDat,
 	 Frm_StartForm (ActFolUsr);
 	 Usr_PutParamUsrCodEncrypted (UsrDat->EncryptedUsrCod);
 	 Frm_LinkFormSubmit (Txt_Follow,"REC_DAT_BOLD",NULL);
-	 fprintf (Gbl.F.Out,"<div class=\"ICO_HIGHLIGHT\""
-			    " style=\"display:inline;\" >");
+	 HTM_DIV_Begin ("class=\"ICO_HIGHLIGHT\" style=\"display:inline;\"");
 	 fprintf (Gbl.F.Out,"<img src=\"%s/user-plus.svg\""
 			    " alt=\"%s\" title=\"%s\""
 			    " class=\"ICO40x40\" />",
@@ -606,7 +604,7 @@ static void Fol_ShowNumberOfFollowingOrFollowers (const struct UsrData *UsrDat,
    extern const char *The_ClassFormOutBoxBold[The_NUM_THEMES];
 
    /***** Start container *****/
-   fprintf (Gbl.F.Out,"<div class=\"FOLLOW_BOX\">");
+   HTM_DIV_Begin ("class=\"FOLLOW_BOX\"");
 
    /***** Number *****/
    if (NumUsrs)
@@ -632,9 +630,9 @@ static void Fol_ShowNumberOfFollowingOrFollowers (const struct UsrData *UsrDat,
       fprintf (Gbl.F.Out,"</span>");
 
    /***** Text *****/
-   fprintf (Gbl.F.Out,"<div class=\"%s\">",
-            (Gbl.Action.Act == Action) ? The_ClassFormOutBoxBold[Gbl.Prefs.Theme] :
-        	                         The_ClassFormOutBox    [Gbl.Prefs.Theme]);
+   HTM_DIV_Begin ("class=\"%s\"",
+                  (Gbl.Action.Act == Action) ? The_ClassFormOutBoxBold[Gbl.Prefs.Theme] :
+        	                               The_ClassFormOutBox    [Gbl.Prefs.Theme]);
    if (NumUsrs)
      {
       /* Form to list users */
@@ -859,7 +857,7 @@ static void Fol_ShowFollowedOrFollower (struct UsrData *UsrDat)
       /* Put form to go to public profile */
       Frm_StartForm (ActSeeOthPubPrf);
       Usr_PutParamUsrCodEncrypted (UsrDat->EncryptedUsrCod);
-      fprintf (Gbl.F.Out,"<div class=\"FOLLOW_USR_NAME\">");	// Limited width
+      HTM_DIV_Begin ("class=\"FOLLOW_USR_NAME\"");	// Limited width
       Frm_LinkFormSubmit (Txt_Another_user_s_profile,"DAT",NULL);
       Usr_WriteFirstNameBRSurnames (UsrDat);
       fprintf (Gbl.F.Out,"</a>");
@@ -916,7 +914,7 @@ static void Fol_WriteRowUsrToFollowOnRightColumn (struct UsrData *UsrDat)
       /* Put form to go to public profile */
       Frm_StartForm (ActSeeOthPubPrf);
       Usr_PutParamUsrCodEncrypted (UsrDat->EncryptedUsrCod);
-      fprintf (Gbl.F.Out,"<div class=\"CON_NAME_FOLLOW\">");	// Limited width
+      HTM_DIV_Begin ("class=\"CON_NAME_FOLLOW\"");	// Limited width
       Frm_LinkFormSubmit (Txt_Another_user_s_profile,"CON_CRS",NULL);
       Usr_WriteFirstNameBRSurnames (UsrDat);
       fprintf (Gbl.F.Out,"</a>");
@@ -954,7 +952,7 @@ static void Fol_WriteRowUsrToFollowOnRightColumn (struct UsrData *UsrDat)
 static void Fol_PutInactiveIconToFollowUnfollow (void)
   {
    /***** Inactive icon to follow/unfollow *****/
-   fprintf (Gbl.F.Out,"<div class=\"FOLLOW_USR_ICO ICO_HIDDEN\">");
+   HTM_DIV_Begin ("class=\"FOLLOW_USR_ICO ICO_HIDDEN\"");
    fprintf (Gbl.F.Out,"<img src=\"%s/user.svg\" alt=\"\" class=\"ICO16x16\" />",
 	    Cfg_URL_ICON_PUBLIC);
    HTM_DIV_End ();
@@ -972,7 +970,7 @@ static void Fol_PutIconToFollow (struct UsrData *UsrDat)
    Frm_StartForm (ActFolUsr);
    Usr_PutParamUsrCodEncrypted (UsrDat->EncryptedUsrCod);
    Frm_LinkFormSubmit (Txt_Follow,NULL,NULL);
-   fprintf (Gbl.F.Out,"<div class=\"FOLLOW_USR_ICO ICO_HIGHLIGHT\">");
+   HTM_DIV_Begin ("class=\"FOLLOW_USR_ICO ICO_HIGHLIGHT\"");
    fprintf (Gbl.F.Out,"<img src=\"%s/user-plus.svg\""
 		      " alt=\"%s\" title=\"%s\" class=\"ICO16x16\" />",
 	    Cfg_URL_ICON_PUBLIC,
@@ -994,7 +992,7 @@ static void Fol_PutIconToUnfollow (struct UsrData *UsrDat)
    Frm_StartForm (ActUnfUsr);
    Usr_PutParamUsrCodEncrypted (UsrDat->EncryptedUsrCod);
    Frm_LinkFormSubmit (Txt_Unfollow,NULL,NULL);
-   fprintf (Gbl.F.Out,"<div class=\"FOLLOW_USR_ICO ICO_HIGHLIGHT\">");
+   HTM_DIV_Begin ("class=\"FOLLOW_USR_ICO ICO_HIGHLIGHT\"");
    fprintf (Gbl.F.Out,"<img src=\"%s/user-check.svg\""
 		      " alt=\"%s\" title=\"%s\" class=\"ICO16x16\" />",
 	    Cfg_URL_ICON_PUBLIC,
diff --git a/swad_forum.c b/swad_forum.c
index 45e48a77..11147e78 100644
--- a/swad_forum.c
+++ b/swad_forum.c
@@ -1440,7 +1440,7 @@ static void For_WriteNumberOfPosts (long UsrCod)
    unsigned NumPsts;
 
    /***** Star table cell *****/
-   fprintf (Gbl.F.Out,"<div class=\"AUTHOR_TXT LT\">");
+   HTM_DIV_Begin ("class=\"AUTHOR_TXT LT\"");
 
    /***** Get number of posts from database *****/
    if (Gbl.Forum.ForumSelected.Location > 0)
@@ -1757,7 +1757,7 @@ static void For_PutFormWhichForums (void)
           - only the forums of current institution/degree/course *****/
    Frm_StartForm (ActSeeFor);
    For_PutParamForumOrder (Gbl.Forum.ThreadsOrder);
-   fprintf (Gbl.F.Out,"<div class=\"SEL_BELOW_TITLE\">");
+   HTM_DIV_Begin ("class=\"SEL_BELOW_TITLE\"");
    fprintf (Gbl.F.Out,"<ul>");
 
    for (ForumSet = (For_ForumSet_t) 0;
diff --git a/swad_game.c b/swad_game.c
index 92d7a685..78c93092 100644
--- a/swad_game.c
+++ b/swad_game.c
@@ -461,9 +461,8 @@ void Gam_ShowOneGame (long GamCod,
    Lay_EndArticle ();
 
    /* Number of questions */
-   fprintf (Gbl.F.Out,"<div class=\"%s\">",
-            Game.Hidden ? "ASG_GRP_LIGHT" :
-        	          "ASG_GRP");
+   HTM_DIV_Begin ("class=\"%s\"",Game.Hidden ? "ASG_GRP_LIGHT" :
+        	                               "ASG_GRP");
    fprintf (Gbl.F.Out,"%s: %u",Txt_No_of_questions,Game.NumQsts);
    HTM_DIV_End ();
 
@@ -511,9 +510,8 @@ void Gam_ShowOneGame (long GamCod,
    Str_ChangeFormat (Str_FROM_HTML,Str_TO_RIGOROUS_HTML,
                      Txt,Cns_MAX_BYTES_TEXT,false);	// Convert from HTML to rigorous HTML
    Str_InsertLinks (Txt,Cns_MAX_BYTES_TEXT,60);	// Insert links
-   fprintf (Gbl.F.Out,"<div class=\"PAR %s\">",
-            Game.Hidden ? "DAT_LIGHT" :
-        	          "DAT");
+   HTM_DIV_Begin ("class=\"PAR %s\"",Game.Hidden ? "DAT_LIGHT" :
+        	                                   "DAT");
    fprintf (Gbl.F.Out,"%s",Txt);
    HTM_DIV_End ();
    HTM_TD_End ();
@@ -1738,13 +1736,13 @@ static void Gam_ListOneOrMoreQuestionsForEdition (long GamCod,unsigned NumQsts,
       HTM_TD_Begin ("class=\"RT COLOR%u\"",Gbl.RowEvenOdd);
 
       /* Write number of question */
-      fprintf (Gbl.F.Out,"<div class=\"BIG_INDEX\">");
+      HTM_DIV_Begin ("class=\"BIG_INDEX\"");
       fprintf (Gbl.F.Out,"%s",StrQstInd);
       HTM_DIV_End ();
 
       /* Write answer type (row[2]) */
       Gbl.Test.AnswerType = Tst_ConvertFromStrAnsTypDBToAnsTyp (row[2]);
-      fprintf (Gbl.F.Out,"<div class=\"DAT_SMALL\">");
+      HTM_DIV_Begin ("class=\"DAT_SMALL\"");
       fprintf (Gbl.F.Out,"%s",Txt_TST_STR_ANSWER_TYPES[Gbl.Test.AnswerType]);
       HTM_DIV_End ();
 
diff --git a/swad_group.c b/swad_group.c
index 21f7b0a1..6202ccd6 100644
--- a/swad_group.c
+++ b/swad_group.c
@@ -410,7 +410,7 @@ void Grp_ShowFormToSelectSeveralGroups (void (*FuncParams) (void),
    Grp_FreeListGrpTypesAndGrps ();
 
    /***** Submit button *****/
-   fprintf (Gbl.F.Out,"<div class=\"CM\" style=\"padding-top:12px;\">");
+   HTM_DIV_Begin ("class=\"CM\" style=\"padding-top:12px;\"");
    Frm_LinkFormSubmitAnimated (Txt_Update_users,
 			       The_ClassFormInBoxBold[Gbl.Prefs.Theme],
 			       "CopyMessageToHiddenFields();");
@@ -452,7 +452,7 @@ static void Grp_PutCheckboxAllGrps (Grp_WhichGroups_t GroupsSelectableByStdsOrNE
 	 break;
      }
 
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_OPT\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_OPT\"");
    fprintf (Gbl.F.Out,"<input type=\"checkbox\""
 		      " id=\"AllGroups\" name=\"AllGroups\" value=\"Y\"");
    if (ICanSelUnselGroup)
@@ -5007,9 +5007,9 @@ void Grp_ShowFormToSelWhichGrps (Act_Action_t Action,void (*FuncParams) (void))
 	WhichGrps <= Grp_ALL_GROUPS;
 	WhichGrps++)
      {
-      fprintf (Gbl.F.Out,"<div class=\"%s\">",
-	       WhichGrps == Gbl.Crs.Grps.WhichGrps ? "PREF_ON" :
-						     "PREF_OFF");
+      HTM_DIV_Begin ("class=\"%s\"",
+	              WhichGrps == Gbl.Crs.Grps.WhichGrps ? "PREF_ON" :
+						            "PREF_OFF");
       Frm_StartForm (Action);
       Par_PutHiddenParamUnsigned ("WhichGrps",(unsigned) WhichGrps);
       if (FuncParams)	// Extra parameters depending on the action
diff --git a/swad_hierarchy.c b/swad_hierarchy.c
index a22ae1a3..98d34910 100644
--- a/swad_hierarchy.c
+++ b/swad_hierarchy.c
@@ -65,7 +65,7 @@ extern struct Globals Gbl;
 void Hie_SeePending (void)
   {
    /***** Put contextual links *****/
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 
    /* Put link to remove old courses */
    Crs_PutLinkToRemoveOldCrss ();
@@ -207,7 +207,7 @@ void Hie_WriteHierarchyInBreadcrumb (void)
    const char *ClassTxt = The_ClassBreadcrumb[Gbl.Prefs.Theme];
 
    /***** Form to go to the system *****/
-   fprintf (Gbl.F.Out,"<div class=\"BC %s\">",ClassTxt);
+   HTM_DIV_Begin ("class=\"BC %s\"",ClassTxt);
    fprintf (Gbl.F.Out,"&nbsp;");
 
    Frm_StartFormGoTo (ActMnu);
@@ -220,7 +220,7 @@ void Hie_WriteHierarchyInBreadcrumb (void)
 
    if (Gbl.Hierarchy.Cty.CtyCod > 0)		// Country selected...
      {
-      fprintf (Gbl.F.Out,"<div class=\"BC %s\">",ClassTxt);
+      HTM_DIV_Begin ("class=\"BC %s\"",ClassTxt);
 
       /***** Separator *****/
       fprintf (Gbl.F.Out,"&nbsp;&gt;&nbsp;");
@@ -236,7 +236,7 @@ void Hie_WriteHierarchyInBreadcrumb (void)
      }
    else
      {
-      fprintf (Gbl.F.Out,"<div class=\"BC BC_SEMIOFF %s\">",ClassTxt);
+      HTM_DIV_Begin ("class=\"BC BC_SEMIOFF %s\"",ClassTxt);
 
       /***** Separator *****/
       fprintf (Gbl.F.Out,"&nbsp;&gt;&nbsp;");
@@ -252,7 +252,7 @@ void Hie_WriteHierarchyInBreadcrumb (void)
 
    if (Gbl.Hierarchy.Ins.InsCod > 0)		// Institution selected...
      {
-      fprintf (Gbl.F.Out,"<div class=\"BC %s\">",ClassTxt);
+      HTM_DIV_Begin ("class=\"BC %s\"",ClassTxt);
 
       /***** Separator *****/
       fprintf (Gbl.F.Out,"&nbsp;&gt;&nbsp;");
@@ -268,7 +268,7 @@ void Hie_WriteHierarchyInBreadcrumb (void)
      }
    else if (Gbl.Hierarchy.Cty.CtyCod > 0)
      {
-      fprintf (Gbl.F.Out,"<div class=\"BC BC_SEMIOFF %s\">",ClassTxt);
+      HTM_DIV_Begin ("class=\"BC BC_SEMIOFF %s\"",ClassTxt);
 
       /***** Separator *****/
       fprintf (Gbl.F.Out,"&nbsp;&gt;&nbsp;");
@@ -283,7 +283,7 @@ void Hie_WriteHierarchyInBreadcrumb (void)
      }
    else
      {
-      fprintf (Gbl.F.Out,"<div class=\"BC BC_OFF %s\">",ClassTxt);
+      HTM_DIV_Begin ("class=\"BC BC_OFF %s\"",ClassTxt);
 
       /***** Separator *****/
       fprintf (Gbl.F.Out,"&nbsp;&gt;&nbsp;");
@@ -296,7 +296,7 @@ void Hie_WriteHierarchyInBreadcrumb (void)
 
    if (Gbl.Hierarchy.Ctr.CtrCod > 0)	// Centre selected...
      {
-      fprintf (Gbl.F.Out,"<div class=\"BC %s\">",ClassTxt);
+      HTM_DIV_Begin ("class=\"BC %s\"",ClassTxt);
 
       /***** Separator *****/
       fprintf (Gbl.F.Out,"&nbsp;&gt;&nbsp;");
@@ -312,7 +312,7 @@ void Hie_WriteHierarchyInBreadcrumb (void)
      }
    else if (Gbl.Hierarchy.Ins.InsCod > 0)
      {
-      fprintf (Gbl.F.Out,"<div class=\"BC BC_SEMIOFF %s\">",ClassTxt);
+      HTM_DIV_Begin ("class=\"BC BC_SEMIOFF %s\"",ClassTxt);
 
       /***** Separator *****/
       fprintf (Gbl.F.Out,"&nbsp;&gt;&nbsp;");
@@ -327,7 +327,7 @@ void Hie_WriteHierarchyInBreadcrumb (void)
      }
    else
      {
-      fprintf (Gbl.F.Out,"<div class=\"BC BC_OFF %s\">",ClassTxt);
+      HTM_DIV_Begin ("class=\"BC BC_OFF %s\"",ClassTxt);
 
       /***** Separator *****/
       fprintf (Gbl.F.Out,"&nbsp;&gt;&nbsp;");
@@ -340,7 +340,7 @@ void Hie_WriteHierarchyInBreadcrumb (void)
 
    if (Gbl.Hierarchy.Deg.DegCod > 0)	// Degree selected...
      {
-      fprintf (Gbl.F.Out,"<div class=\"BC %s\">",ClassTxt);
+      HTM_DIV_Begin ("class=\"BC %s\"",ClassTxt);
 
       /***** Separator *****/
       fprintf (Gbl.F.Out,"&nbsp;&gt;&nbsp;");
@@ -356,7 +356,7 @@ void Hie_WriteHierarchyInBreadcrumb (void)
      }
    else if (Gbl.Hierarchy.Ctr.CtrCod > 0)
      {
-      fprintf (Gbl.F.Out,"<div class=\"BC BC_SEMIOFF %s\">",ClassTxt);
+      HTM_DIV_Begin ("class=\"BC BC_SEMIOFF %s\"",ClassTxt);
 
       /***** Separator *****/
       fprintf (Gbl.F.Out,"&nbsp;&gt;&nbsp;");
@@ -371,7 +371,7 @@ void Hie_WriteHierarchyInBreadcrumb (void)
      }
    else
      {
-      fprintf (Gbl.F.Out,"<div class=\"BC BC_OFF %s\">",ClassTxt);
+      HTM_DIV_Begin ("class=\"BC BC_OFF %s\"",ClassTxt);
 
       /***** Separator *****/
       fprintf (Gbl.F.Out,"&nbsp;&gt;&nbsp;");
@@ -382,11 +382,11 @@ void Hie_WriteHierarchyInBreadcrumb (void)
       HTM_DIV_End ();
      }
 
-   fprintf (Gbl.F.Out,"<div class=\"BC%s %s\">",
-	     (Gbl.Hierarchy.Level == Hie_CRS) ? "" :
-            ((Gbl.Hierarchy.Deg.DegCod > 0) ? " BC_SEMIOFF" :
-		                              " BC_OFF"),
-            ClassTxt);
+   HTM_DIV_Begin ("class=\"BC%s %s\"",
+		   (Gbl.Hierarchy.Level == Hie_CRS) ? "" :
+		  ((Gbl.Hierarchy.Deg.DegCod > 0) ? " BC_SEMIOFF" :
+						    " BC_OFF"),
+		  ClassTxt);
 
    /***** Separator *****/
    fprintf (Gbl.F.Out,"&nbsp;&gt;&nbsp;");
@@ -437,10 +437,10 @@ void Hie_WriteBigNameCtyInsCtrDegCrs (void)
      }
 
    /***** Text *****/
-   fprintf (Gbl.F.Out,"<div id=\"big_name_container\">");
+   HTM_DIV_Begin ("id=\"big_name_container\"");
    if (Gbl.Hierarchy.Cty.CtyCod > 0)
      {
-      fprintf (Gbl.F.Out,"<div id=\"big_full_name\">");
+      HTM_DIV_Begin ("id=\"big_full_name\"");
       fprintf (Gbl.F.Out,"%s",		// Full name
 		(Gbl.Hierarchy.Level == Hie_CRS) ? Gbl.Hierarchy.Crs.FullName :
 	       ((Gbl.Hierarchy.Level == Hie_DEG) ? Gbl.Hierarchy.Deg.FullName :
@@ -448,10 +448,12 @@ void Hie_WriteBigNameCtyInsCtrDegCrs (void)
 	       ((Gbl.Hierarchy.Level == Hie_INS) ? Gbl.Hierarchy.Ins.FullName :
 	                                           Gbl.Hierarchy.Cty.Name[Gbl.Prefs.Language]))));
       HTM_DIV_End ();
-      fprintf (Gbl.F.Out,"<div class=\"NOT_SHOWN\">");
+
+      HTM_DIV_Begin ("class=\"NOT_SHOWN\"");
       fprintf (Gbl.F.Out," / ");	// To separate
       HTM_DIV_End ();
-      fprintf (Gbl.F.Out,"<div id=\"big_short_name\">");
+
+      HTM_DIV_Begin ("id=\"big_short_name\"");
       fprintf (Gbl.F.Out,"%s",		// Short name
 		(Gbl.Hierarchy.Level == Hie_CRS) ? Gbl.Hierarchy.Crs.ShrtName :
 	       ((Gbl.Hierarchy.Level == Hie_DEG) ? Gbl.Hierarchy.Deg.ShrtName :
@@ -462,14 +464,16 @@ void Hie_WriteBigNameCtyInsCtrDegCrs (void)
      }
    else	// No country specified ==> home page
      {
-      fprintf (Gbl.F.Out,"<div id=\"big_full_name\">");
+      HTM_DIV_Begin ("id=\"big_full_name\"");
       fprintf (Gbl.F.Out,"%s: %s",	// Full name
 	       Cfg_PLATFORM_SHORT_NAME,Txt_TAGLINE);
       HTM_DIV_End ();
-      fprintf (Gbl.F.Out,"<div class=\"NOT_SHOWN\">");
+
+      HTM_DIV_Begin ("class=\"NOT_SHOWN\"");
       fprintf (Gbl.F.Out," / ");	// To separate
       HTM_DIV_End ();
-      fprintf (Gbl.F.Out,"<div id=\"big_short_name\">");
+
+      HTM_DIV_Begin ("id=\"big_short_name\"");
       fprintf (Gbl.F.Out,"%s",		// Short name
 	       Cfg_PLATFORM_SHORT_NAME);
       HTM_DIV_End ();
diff --git a/swad_icon.c b/swad_icon.c
index 6450ea63..cc619461 100644
--- a/swad_icon.c
+++ b/swad_icon.c
@@ -124,9 +124,9 @@ void Ico_PutIconsToSelectIconSet (void)
 	IconSet < Ico_NUM_ICON_SETS;
 	IconSet++)
      {
-      fprintf (Gbl.F.Out,"<div class=\"%s\">",
-               IconSet == Gbl.Prefs.IconSet ? "PREF_ON" :
-        	                              "PREF_OFF");
+      HTM_DIV_Begin ("class=\"%s\"",
+                     IconSet == Gbl.Prefs.IconSet ? "PREF_ON" :
+        	                                    "PREF_OFF");
       Frm_StartForm (ActChgIco);
       Par_PutHiddenParamString ("IconSet",Ico_IconSetId[IconSet]);
       snprintf (Icon,sizeof (Icon),
@@ -332,7 +332,7 @@ void Ico_PutContextualIconToZIP (Act_Action_t NextAction,void (*FuncParams) (voi
 
 void Ico_PutDivIcon (const char *DivClass,const char *Icon,const char *Title)
   {
-   fprintf (Gbl.F.Out,"<div class=\"%s\">",DivClass);
+   HTM_DIV_Begin ("class=\"%s\"",DivClass);
    fprintf (Gbl.F.Out,"<img src=\"%s/%s\" alt=\"%s\" title=\"%s\""
 		      " class=\"CONTEXT_ICO_16x16\" />",
 	    Cfg_URL_ICON_PUBLIC,Icon,
@@ -346,7 +346,7 @@ void Ico_PutDivIcon (const char *DivClass,const char *Icon,const char *Title)
 
 void Ico_PutDivIconLink (const char *DivClass,const char *Icon,const char *Title)
   {
-   fprintf (Gbl.F.Out,"<div class=\"%s\">",DivClass);
+   HTM_DIV_Begin ("class=\"%s\"",DivClass);
    Ico_PutIconLink (Icon,Title);
    HTM_DIV_End ();
   }
@@ -371,7 +371,7 @@ void Ico_PutIconLink (const char *Icon,const char *Title)
 void Ico_PutIconTextLink (const char *Icon,const char *Text)
   {
    /***** Print icon and optional text *****/
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_OPT ICO_HIGHLIGHT\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_OPT ICO_HIGHLIGHT\"");
    fprintf (Gbl.F.Out,"<img src=\"%s/%s\" alt=\"%s\" title=\"%s\""
 	              " class=\"CONTEXT_ICO_x16\" />"
 	              "&nbsp;%s",
@@ -411,7 +411,7 @@ void Ico_PutIconOff (const char *Icon,const char *Title)
 
 void Ico_PutCalculateIcon (const char *Title)
   {
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_OPT ICO_HIGHLIGHT\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_OPT ICO_HIGHLIGHT\"");
    fprintf (Gbl.F.Out,"<img id=\"update_%d\" src=\"%s/recycle16x16.gif\""	// TODO: change name and resolution to refresh64x64.png
 	              " alt=\"%s\" title=\"%s\""
 		      " class=\"CONTEXT_ICO_16x16\" />"
@@ -432,8 +432,7 @@ void Ico_PutCalculateIcon (const char *Title)
 
 void Ico_PutCalculateIconWithText (const char *Text)
   {
-   fprintf (Gbl.F.Out,"<div class=\"ICO_HIGHLIGHT\""
-	              " style=\"margin:0 6px 0 0; display:inline;\">");
+   HTM_DIV_Begin ("class=\"ICO_HIGHLIGHT\" style=\"margin:0 6px 0 0; display:inline;\"");
    fprintf (Gbl.F.Out,"<img id=\"update_%d\" src=\"%s/recycle16x16.gif\""
 	              " alt=\"%s\" title=\"%s\""
 		      " class=\"ICO20x20\" />"
diff --git a/swad_info.c b/swad_info.c
index 8a8796c2..49e160e9 100644
--- a/swad_info.c
+++ b/swad_info.c
@@ -384,7 +384,7 @@ void Inf_ShowInfo (void)
          /* Put checkbox to force students to read this couse info */
          if (MustBeRead)
            {
-            fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+            HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
             Inf_PutCheckboxConfirmIHaveReadInfo ();
             HTM_DIV_End ();
            }
@@ -395,7 +395,7 @@ void Inf_ShowInfo (void)
          /* Put checkbox to force students to read this couse info */
          if (InfoSrc != Inf_INFO_SRC_NONE)
            {
-            fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+            HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
             Disabled = (Gbl.Usrs.Me.Role.Logged == Rol_NET);	// Non-editing teachers can not change the status of checkbox
             Inf_PutCheckboxForceStdsToReadInfo (MustBeRead,Disabled);
             HTM_DIV_End ();
@@ -599,7 +599,7 @@ void Inf_WriteMsgYouMustReadInfo (void)
    Ale_ShowAlert (Ale_WARNING,Txt_You_should_read_the_following_information);
 
    /***** Write every information I must read *****/
-   fprintf (Gbl.F.Out,"<div class=\"CM\">");
+   HTM_DIV_Begin ("class=\"CM\"");
    fprintf (Gbl.F.Out,"<ul class=\"LIST_LEFT\""
 	              " style=\"list-style-type:initial;\">");
    for (InfoType = (Inf_InfoType_t) 0;
@@ -1272,7 +1272,7 @@ void Inf_FormToSendPage (Inf_InfoSrc_t InfoSrc)
    Frm_StartForm (Inf_ActionsInfo[InfoSrc][Gbl.Crs.Info.Type]);
 
    /***** File *****/
-   fprintf (Gbl.F.Out,"<div class=\"CM\">");
+   HTM_DIV_Begin ("class=\"CM\"");
    fprintf (Gbl.F.Out,"<label class=\"%s\">"
                       "%s:&nbsp;"
                       "<input type=\"file\" name=\"%s\" />"
@@ -1307,7 +1307,7 @@ void Inf_FormToSendURL (Inf_InfoSrc_t InfoSrc)
    Frm_StartForm (Inf_ActionsInfo[InfoSrc][Gbl.Crs.Info.Type]);
 
    /***** Link *****/
-   fprintf (Gbl.F.Out,"<div class=\"CM\">");
+   HTM_DIV_Begin ("class=\"CM\"");
    fprintf (Gbl.F.Out,"<label class=\"%s\">"
                       "%s:&nbsp;"
                       "<input type=\"url\" name=\"InfoSrcURL\""
@@ -1798,7 +1798,7 @@ static bool Inf_CheckAndShowPlainTxt (void)
           Gbl.Crs.Info.Type == Inf_TEACHING_GUIDE)
          Lay_WriteHeaderClassPhoto (false,false,Gbl.Hierarchy.Ins.InsCod,Gbl.Hierarchy.Deg.DegCod,Gbl.Hierarchy.Crs.CrsCod);
 
-      fprintf (Gbl.F.Out,"<div class=\"DAT LM\">");
+      HTM_DIV_Begin ("class=\"DAT LM\"");
 
       /***** Convert to respectful HTML and insert links *****/
       Str_ChangeFormat (Str_FROM_HTML,Str_TO_RIGOROUS_HTML,
@@ -1882,7 +1882,7 @@ static bool Inf_CheckAndShowRichTxt (void)
           Gbl.Crs.Info.Type == Inf_TEACHING_GUIDE)
          Lay_WriteHeaderClassPhoto (false,false,Gbl.Hierarchy.Ins.InsCod,Gbl.Hierarchy.Deg.DegCod,Gbl.Hierarchy.Crs.CrsCod);
 
-      fprintf (Gbl.F.Out,"<div id=\"crs_info\" class=\"LM\">");
+      HTM_DIV_Begin ("id=\"crs_info\" class=\"LM\"");
 
       /***** Store text into a temporary .md file in HTML output directory *****/
       // TODO: change to another directory?
@@ -2078,7 +2078,7 @@ void Inf_EditPlainTxtInfo (void)
                          TxtHTML,NULL);
 
    /***** Edition area *****/
-   fprintf (Gbl.F.Out,"<div class=\"CM\">");
+   HTM_DIV_Begin ("class=\"CM\"");
    Lay_HelpPlainEditor ();
    fprintf (Gbl.F.Out,"<textarea name=\"Txt\" cols=\"80\" rows=\"20\">"
 	              "%s"
@@ -2129,7 +2129,7 @@ void Inf_EditRichTxtInfo (void)
                          TxtHTML,NULL);
 
    /***** Edition area *****/
-   fprintf (Gbl.F.Out,"<div class=\"CM\">");
+   HTM_DIV_Begin ("class=\"CM\"");
    Lay_HelpRichEditor ();
    fprintf (Gbl.F.Out,"<textarea name=\"Txt\" cols=\"80\" rows=\"20\">"
 	              "%s"
diff --git a/swad_institution.c b/swad_institution.c
index e2359bcb..78f89a37 100644
--- a/swad_institution.c
+++ b/swad_institution.c
@@ -334,7 +334,7 @@ static void Ins_Configuration (bool PrintView)
 
    /***** Title *****/
    PutLink = !PrintView && Gbl.Hierarchy.Ins.WWW[0];
-   fprintf (Gbl.F.Out,"<div class=\"FRAME_TITLE FRAME_TITLE_BIG\">");
+   HTM_DIV_Begin ("class=\"FRAME_TITLE FRAME_TITLE_BIG\"");
    if (PutLink)
       fprintf (Gbl.F.Out,"<a href=\"%s\" target=\"_blank\""
 			 " class=\"FRAME_TITLE_BIG\" title=\"%s\">",
@@ -485,7 +485,7 @@ static void Ins_Configuration (bool PrintView)
      }
    else	// I can not change institution WWW
      {
-      fprintf (Gbl.F.Out,"<div class=\"EXTERNAL_WWW_LONG\">");
+      HTM_DIV_Begin ("class=\"EXTERNAL_WWW_LONG\"");
       fprintf (Gbl.F.Out,"<a href=\"%s\" target=\"_blank\" class=\"DAT\">"
 			 "%s"
 			 "</a>",
@@ -1555,7 +1555,7 @@ static void Ins_ListInstitutionsForEdition (void)
 	{
          Str_Copy (WWW,Ins->WWW,
                    Cns_MAX_BYTES_WWW);
-         fprintf (Gbl.F.Out,"<div class=\"EXTERNAL_WWW_SHORT\">");
+         HTM_DIV_Begin ("class=\"EXTERNAL_WWW_SHORT\"");
          fprintf (Gbl.F.Out,"<a href=\"%s\" target=\"_blank\""
                             " class=\"DAT\" title=\"%s\">"
                             "%s"
diff --git a/swad_layout.c b/swad_layout.c
index ea42e07e..2a79aaf7 100644
--- a/swad_layout.c
+++ b/swad_layout.c
@@ -271,12 +271,12 @@ void Lay_WriteStartOfPage (void)
      {
       case Act_BRW_1ST_TAB:
 	 fprintf (Gbl.F.Out,"<body onload=\"init();\">\n");
-	 fprintf (Gbl.F.Out,"<div id=\"zoomLyr\" class=\"ZOOM\">");
+	 HTM_DIV_Begin ("id=\"zoomLyr\" class=\"ZOOM\"");
 	 fprintf (Gbl.F.Out,"<img id=\"zoomImg\" src=\"%s/usr_bl.jpg\""
 			    " alt=\"\" title=\"\""
 			    " class=\"IMG_USR\" />",
 		  Cfg_URL_ICON_PUBLIC);
-	 fprintf (Gbl.F.Out,"<div id=\"zoomTxt\" class=\"CM\">");
+	 HTM_DIV_Begin ("id=\"zoomTxt\" class=\"CM\"");
 	 HTM_DIV_End ();
 	 HTM_DIV_End ();
 	 break;
@@ -296,7 +296,7 @@ void Lay_WriteStartOfPage (void)
      }
 
    /***** Start box that contains the whole page except the foot *****/
-   fprintf (Gbl.F.Out,"<div id=\"whole_page\">");
+   HTM_DIV_Begin ("id=\"whole_page\"");
 
    /***** Header of layout *****/
    Lay_WritePageTopHeading ();
@@ -305,7 +305,7 @@ void Lay_WriteStartOfPage (void)
    Tab_DrawTabs ();
 
    /***** 4th row: main zone *****/
-   fprintf (Gbl.F.Out,"<div id=\"main_zone\">");
+   HTM_DIV_Begin ("id=\"main_zone\"");
 
    /* Left column */
    if (Gbl.Prefs.SideCols & Lay_SHOW_LEFT_COLUMN)		// Left column visible
@@ -331,29 +331,29 @@ void Lay_WriteStartOfPage (void)
    switch (Gbl.Prefs.SideCols)
      {
       case 0:
-         fprintf (Gbl.F.Out,"<div id=\"main_zone_central_none\">");
+         HTM_DIV_Begin ("id=\"main_zone_central_none\"");
 	 break;
       case Lay_SHOW_LEFT_COLUMN:
-         fprintf (Gbl.F.Out,"<div id=\"main_zone_central_left\">");
+         HTM_DIV_Begin ("id=\"main_zone_central_left\"");
 	 break;
       case Lay_SHOW_RIGHT_COLUMN:
-         fprintf (Gbl.F.Out,"<div id=\"main_zone_central_right\">");
+         HTM_DIV_Begin ("id=\"main_zone_central_right\"");
 	 break;
       case (Lay_SHOW_LEFT_COLUMN | Lay_SHOW_RIGHT_COLUMN):
-         fprintf (Gbl.F.Out,"<div id=\"main_zone_central_both\">");
+         HTM_DIV_Begin ("id=\"main_zone_central_both\"");
          break;
      }
-   fprintf (Gbl.F.Out,"<div id=\"main_zone_central_container\" class=\"%s\">",
-	    The_TabOnBgColors[Gbl.Prefs.Theme]);
+   HTM_DIV_Begin ("id=\"main_zone_central_container\" class=\"%s\"",
+	          The_TabOnBgColors[Gbl.Prefs.Theme]);
 
    /* Layout with horizontal or vertical menu */
-   fprintf (Gbl.F.Out,"<div id=\"%s\">",LayoutMainZone[Gbl.Prefs.Menu]);
+   HTM_DIV_Begin ("id=\"%s\"",LayoutMainZone[Gbl.Prefs.Menu]);
 
    /* Menu */
    Mnu_WriteMenuThisTab ();
 
    /* Start canvas: main zone for actions output */
-   fprintf (Gbl.F.Out,"<div class=\"MAIN_ZONE_CANVAS\">");
+   HTM_DIV_Begin ("class=\"MAIN_ZONE_CANVAS\"");
 
    /* If it is mandatory to read any information about course */
    if (Gbl.Crs.Info.ShowMsgMustBeRead)
@@ -923,17 +923,16 @@ static void Lay_WritePageTopHeading (void)
 
    /***** 1st. row *****/
    /* Start 1st. row */
-   fprintf (Gbl.F.Out,"<div id=\"head_row_1\" class=\"%s\">",
-            ClassHeadRow1[Gbl.Prefs.Theme]);
+   HTM_DIV_Begin ("id=\"head_row_1\" class=\"%s\"",ClassHeadRow1[Gbl.Prefs.Theme]);
 
    /* 1st. row, 1st. column: logo, tagline and search */
-   fprintf (Gbl.F.Out,"<div id=\"head_row_1_left\">");
+   HTM_DIV_Begin ("id=\"head_row_1_left\"");
 
    /* Begin form to go to home page */
    Frm_StartFormGoTo (ActMnu);
    Par_PutHiddenParamUnsigned ("NxtTab",(unsigned) TabSys);
 
-   fprintf (Gbl.F.Out,"<div id=\"head_row_1_logo_small\">");
+   HTM_DIV_Begin ("id=\"head_row_1_logo_small\"");
    Frm_LinkFormSubmit (Txt_System,NULL,NULL);
    fprintf (Gbl.F.Out,"<img src=\"%s/%s\" alt=\"%s\" title=\"%s\""
                       " class=\"CM\""
@@ -943,7 +942,7 @@ static void Lay_WritePageTopHeading (void)
             Cfg_PLATFORM_SHORT_NAME,Cfg_PLATFORM_FULL_NAME,
             Cfg_PLATFORM_LOGO_SMALL_WIDTH,Cfg_PLATFORM_LOGO_SMALL_HEIGHT);
    HTM_DIV_End ();
-   fprintf (Gbl.F.Out,"<div id=\"head_row_1_logo_big\">");
+   HTM_DIV_Begin ("id=\"head_row_1_logo_big\"");
    Frm_LinkFormSubmit (Txt_System,NULL,NULL);
    fprintf (Gbl.F.Out,"<img src=\"%s/%s\" alt=\"%s\" title=\"%s\""
                       " class=\"CM\""
@@ -953,7 +952,7 @@ static void Lay_WritePageTopHeading (void)
             Cfg_PLATFORM_SHORT_NAME,Cfg_PLATFORM_FULL_NAME,
             Cfg_PLATFORM_LOGO_BIG_WIDTH,Cfg_PLATFORM_LOGO_BIG_HEIGHT);
    HTM_DIV_End ();
-   fprintf (Gbl.F.Out,"<div id=\"head_row_1_tagline\">");
+   HTM_DIV_Begin ("id=\"head_row_1_tagline\"");
    Frm_LinkFormSubmit (Txt_TAGLINE,The_ClassTagline[Gbl.Prefs.Theme],NULL);
    fprintf (Gbl.F.Out,"%s"
 	              "</a>",
@@ -969,13 +968,13 @@ static void Lay_WritePageTopHeading (void)
 
    /* 1st. row, 3rd. column: logged user or language selection,
       and link to open/close session */
-   fprintf (Gbl.F.Out,"<div id=\"head_row_1_right\">");
+   HTM_DIV_Begin ("id=\"head_row_1_right\"");
    if (Gbl.Usrs.Me.Logged)
       Usr_WriteLoggedUsrHead ();
    else
       Lan_PutSelectorToSelectLanguage ();
 
-   fprintf (Gbl.F.Out,"<div id=\"login_box\">");
+   HTM_DIV_Begin ("id=\"login_box\"");
    if (Gbl.Usrs.Me.Logged)
       Usr_PutFormLogOut ();
    else
@@ -988,23 +987,22 @@ static void Lay_WritePageTopHeading (void)
 
    /***** 2nd. row *****/
    /* Start second row */
-   fprintf (Gbl.F.Out,"<div id=\"head_row_2\" class=\"%s\">",
-            ClassHeadRow2[Gbl.Prefs.Theme]);
+   HTM_DIV_Begin ("id=\"head_row_2\" class=\"%s\"",ClassHeadRow2[Gbl.Prefs.Theme]);
 
    /* 2nd. row, 1st. column
       Clock with hour:minute (server hour is shown) */
-   fprintf (Gbl.F.Out,"<div id=\"head_row_2_time\">");
+   HTM_DIV_Begin ("id=\"head_row_2_time\"");
    Dat_ShowClientLocalTime ();
    HTM_DIV_End ();	// End first column
 
    /* 2nd. row, 2nd. column: degree and course */
-   fprintf (Gbl.F.Out,"<div id=\"head_row_2_hierarchy\">");
+   HTM_DIV_Begin ("id=\"head_row_2_hierarchy\"");
    Lay_WriteBreadcrumb ();
    Hie_WriteBigNameCtyInsCtrDegCrs ();
    HTM_DIV_End ();
 
    /* 2nd. row, 3rd. column */
-   fprintf (Gbl.F.Out,"<div id=\"msg\">");	// Used for AJAX based refresh
+   HTM_DIV_Begin ("id=\"msg\"");	// Used for AJAX based refresh
    if (Gbl.Usrs.Me.Logged)
       Ntf_WriteNumberOfNewNtfs ();
    HTM_DIV_End ();		// Used for AJAX based refresh
@@ -1040,24 +1038,20 @@ static void Lay_WriteTitleAction (void)
    extern const char *Txt_TABS_TXT[Tab_NUM_TABS];
 
    /***** Container start *****/
-   fprintf (Gbl.F.Out,"<div id=\"action_title\""
-	              " style=\"background-image:url('%s/%s');\">",
-	    Gbl.Prefs.URLIconSet,
-	    Act_GetIcon (Act_GetSuperAction (Gbl.Action.Act)));
+   HTM_DIV_Begin ("id=\"action_title\" style=\"background-image:url('%s/%s');\"",
+	          Gbl.Prefs.URLIconSet,
+	          Act_GetIcon (Act_GetSuperAction (Gbl.Action.Act)));
 
    /***** Title *****/
-   fprintf (Gbl.F.Out,"<div class=\"%s\">",
-	    The_ClassTitleAction[Gbl.Prefs.Theme]);
+   HTM_DIV_Begin ("class=\"%s\"",The_ClassTitleAction[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s &gt; %s",
 	    Txt_TABS_TXT[Act_GetTab (Gbl.Action.Act)],
 	    Act_GetTitleAction (Gbl.Action.Act));
    HTM_DIV_End ();
 
    /***** Subtitle *****/
-   fprintf (Gbl.F.Out,"<div class=\"%s\">",
-	    The_ClassSubtitleAction[Gbl.Prefs.Theme]);
-   fprintf (Gbl.F.Out,"%s",
-	    Act_GetSubtitleAction (Gbl.Action.Act));
+   HTM_DIV_Begin ("class=\"%s\"",The_ClassSubtitleAction[Gbl.Prefs.Theme]);
+   fprintf (Gbl.F.Out,"%s",Act_GetSubtitleAction (Gbl.Action.Act));
    HTM_DIV_End ();
 
    /***** Container end *****/
@@ -1072,9 +1066,9 @@ static void Lay_ShowLeftColumn (void)
   {
    struct MFU_ListMFUActions ListMFUActions;
 
-   fprintf (Gbl.F.Out,"<div style=\"width:160px;\">");
+   HTM_DIV_Begin ("style=\"width:160px;\"");
 
-   fprintf (Gbl.F.Out,"<div class=\"LEFT_RIGHT_CELL\">");
+   HTM_DIV_Begin ("class=\"LEFT_RIGHT_CELL\"");
    if (Gbl.Usrs.Me.Logged)
      {
       /***** Most frequently used actions *****/
@@ -1089,14 +1083,14 @@ static void Lay_ShowLeftColumn (void)
    HTM_DIV_End ();
 
    /***** Month *****/
-   fprintf (Gbl.F.Out,"<div class=\"LEFT_RIGHT_CELL\">");
+   HTM_DIV_Begin ("class=\"LEFT_RIGHT_CELL\"");
    Cal_DrawCurrentMonth ();
    HTM_DIV_End ();
 
    /***** Notices (yellow notes) *****/
    if (Gbl.Hierarchy.Level == Hie_CRS)
      {
-      fprintf (Gbl.F.Out,"<div class=\"LEFT_RIGHT_CELL\">");
+      HTM_DIV_Begin ("class=\"LEFT_RIGHT_CELL\"");
       Not_ShowNotices (Not_LIST_BRIEF_NOTICES,
 	               -1L);	// No notice highlighted
       HTM_DIV_End ();
@@ -1121,20 +1115,18 @@ static void Lay_ShowRightColumn (void)
    /***** Number of connected users in the whole platform *****/
    if (Gbl.Usrs.Me.Role.Logged == Rol_SYS_ADM)
      {
-      fprintf (Gbl.F.Out,"<div id=\"globalconnected\""	// Used for AJAX based refresh
-			 " class=\"LEFT_RIGHT_CELL\">");
+      HTM_DIV_Begin ("id=\"globalconnected\" class=\"LEFT_RIGHT_CELL\"");	// Used for AJAX based refresh
       Con_ShowGlobalConnectedUsrs ();
-      HTM_DIV_End ();			// Used for AJAX based refresh
+      HTM_DIV_End ();								// Used for AJAX based refresh
      }
 
    /***** Number of connected users in the current course *****/
    if (Gbl.Hierarchy.Level == Hie_CRS)	// There is a course selected
      {
-      fprintf (Gbl.F.Out,"<div id=\"courseconnected\""	// Used for AJAX based refresh
-	                 " class=\"LEFT_RIGHT_CELL\">");
+      HTM_DIV_Begin ("id=\"courseconnected\" class=\"LEFT_RIGHT_CELL\"");	// Used for AJAX based refresh
       Gbl.Scope.Current = Hie_CRS;
       Con_ShowConnectedUsrsBelongingToCurrentCrs ();
-      HTM_DIV_End ();			// Used for AJAX based refresh
+      HTM_DIV_End ();								// Used for AJAX based refresh
      }
    else if (Gbl.Usrs.Me.Logged)		// I am logged
      {
@@ -1142,7 +1134,7 @@ static void Lay_ShowRightColumn (void)
       gettimeofday (&tv1,NULL);
       */
       /***** Suggest one user to follow *****/
-      fprintf (Gbl.F.Out,"<div class=\"LEFT_RIGHT_CELL\">");
+      HTM_DIV_Begin ("class=\"LEFT_RIGHT_CELL\"");
       Fol_SuggestUsrsToFollowMainZoneOnRightColumn ();
       /*
       gettimeofday (&tv2,NULL);
@@ -1162,7 +1154,7 @@ static void Lay_ShowRightColumn (void)
    if (!Gbl.Usrs.Me.Logged)
      {
       /***** SWADroid advertisement *****/
-      fprintf (Gbl.F.Out,"<div class=\"LEFT_RIGHT_CELL\">");
+      HTM_DIV_Begin ("class=\"LEFT_RIGHT_CELL\"");
       fprintf (Gbl.F.Out,"<a href=\"https://play.google.com/store/apps/details?id=es.ugr.swad.swadroid\""
 			 " target=\"_blank\" title=\"%s\">"
 			 "<img src=\"%s/SWADroid120x200.png\""
@@ -1286,11 +1278,11 @@ void Lay_PutContextualCheckbox (Act_Action_t NextAction,
       FuncParams ();
 
    /***** Start container and label *****/
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_OPT %s %s\" title=\"%s\">",
-            Checked ? "CHECKBOX_CHECKED" :
-        	      "CHECKBOX_UNCHECKED",
-            The_ClassFormOutBoxBold[Gbl.Prefs.Theme],
-            Title);
+   HTM_DIV_Begin ("class=\"CONTEXT_OPT %s %s\" title=\"%s\"",
+		  Checked ? "CHECKBOX_CHECKED" :
+			    "CHECKBOX_UNCHECKED",
+		  The_ClassFormOutBoxBold[Gbl.Prefs.Theme],
+		  Title);
    fprintf (Gbl.F.Out,"<label>");
 
    /****** Checkbox and text *****/
@@ -1715,7 +1707,7 @@ void Lay_AdvertisementMobile (void)
 
    if (!(rand () % Lay_SHOW_ADVERTISEMENT_ONE_TIME_OF_X))
      {
-      fprintf (Gbl.F.Out,"<div style=\"margin-top:25px;\">");
+      HTM_DIV_Begin ("style=\"margin-top:25px;\"");
 
       /***** Start box and table *****/
       Box_StartBoxTable (NULL,NULL,NULL,
@@ -1801,7 +1793,7 @@ static void Lay_HelpTextEditor (const char *Text,const char *InlineMath,const ch
    extern const char *Txt_Inline_math;
    extern const char *Txt_Equation_centered;
 
-   fprintf (Gbl.F.Out,"<div class=\"HELP_EDIT\">");
+   HTM_DIV_Begin ("class=\"HELP_EDIT\"");
    fprintf (Gbl.F.Out,"%s: %s"
                       " "
                       "%s: <code>%s</code>"
diff --git a/swad_link.c b/swad_link.c
index e9de7616..b9385e25 100644
--- a/swad_link.c
+++ b/swad_link.c
@@ -162,7 +162,7 @@ void Lnk_WriteMenuWithInstitutionalLinks (void)
    /***** Write all the links *****/
    if (Gbl.Links.Num)
      {
-      fprintf (Gbl.F.Out,"<div id=\"institutional_links\">");
+      HTM_DIV_Begin ("id=\"institutional_links\"");
 
       Frm_StartForm (ActSeeLnk);
       Frm_LinkFormSubmit (Txt_Links,NULL,NULL);
diff --git a/swad_logo.c b/swad_logo.c
index 879083a6..e38f470b 100644
--- a/swad_logo.c
+++ b/swad_logo.c
@@ -278,7 +278,7 @@ void Log_RequestLogo (Hie_Level_t Scope)
    if (Fil_CheckIfPathExists (PathLogo))
      {
       /***** Form to remove photo *****/
-      fprintf (Gbl.F.Out,"<div class=\"CM\">");
+      HTM_DIV_Begin ("class=\"CM\"");
       Lay_PutContextualLinkIconText (ActionRem,NULL,NULL,
 				     "trash.svg",
 				     Txt_Remove_logo);
diff --git a/swad_mail.c b/swad_mail.c
index 16d48571..b464331d 100644
--- a/swad_mail.c
+++ b/swad_mail.c
@@ -922,7 +922,7 @@ static void Mai_ListEmails (void)
 		 Hlp_MESSAGES_Email,Box_NOT_CLOSABLE);
 
    /***** Start list with users' email addresses *****/
-   fprintf (Gbl.F.Out,"<div class=\"DAT_SMALL CM\">");
+   HTM_DIV_Begin ("class=\"DAT_SMALL CM\"");
 
    /***** Initialize structure with user's data *****/
    Usr_UsrDataConstructor (&UsrDat);
@@ -978,19 +978,18 @@ static void Mai_ListEmails (void)
    HTM_DIV_End ();
 
    /***** Show a message with the number of users with email ****/
-   fprintf (Gbl.F.Out,"<div class=\"DAT CM\">");
-   fprintf (Gbl.F.Out,Txt_X_users_who_have_email,
-	    NumUsrsWithEmail);
+   HTM_DIV_Begin ("class=\"DAT CM\"");
+   fprintf (Gbl.F.Out,Txt_X_users_who_have_email,NumUsrsWithEmail);
    HTM_DIV_End ();
 
    /***** Show a message with the number of users who have accepted and have email ****/
-   fprintf (Gbl.F.Out,"<div class=\"DAT CM\">");
+   HTM_DIV_Begin ("class=\"DAT CM\"");
    fprintf (Gbl.F.Out,Txt_X_users_who_have_accepted_and_who_have_email,
 	    NumAcceptedUsrsWithEmail);
    HTM_DIV_End ();
 
    /***** Icon to open the client email program *****/
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
    fprintf (Gbl.F.Out,"<a href=\"mailto:%s?subject=%s&cc=%s&bcc=%s\""
 		      " title=\"%s\" class=\"%s\">",
 	    Gbl.Usrs.Me.UsrDat.Email,
diff --git a/swad_match.c b/swad_match.c
index d9af0dde..28737dba 100644
--- a/swad_match.c
+++ b/swad_match.c
@@ -609,10 +609,9 @@ static void Mch_GetAndWriteNamesOfGrpsAssociatedToMatch (const struct Match *Mat
 			     Match->MchCod);
 
    /***** Write heading *****/
-   fprintf (Gbl.F.Out,"<div class=\"ASG_GRP\">");
-   fprintf (Gbl.F.Out,"%s: ",
-            NumRows == 1 ? Txt_Group  :
-                           Txt_Groups);
+   HTM_DIV_Begin ("class=\"ASG_GRP\"");
+   fprintf (Gbl.F.Out,"%s: ",NumRows == 1 ? Txt_Group  :
+                                            Txt_Groups);
 
    /***** Write groups *****/
    if (NumRows) // Groups found...
@@ -675,7 +674,7 @@ static void Mch_ListOneOrMoreMatchesStatus (const struct Match *Match,unsigned N
    if (Match->Status.QstInd < Mch_AFTER_LAST_QUESTION)	// Unfinished match
      {
       /* Current question index / total of questions */
-      fprintf (Gbl.F.Out,"<div class=\"DAT\">");
+      HTM_DIV_Begin ("class=\"DAT\"");
       fprintf (Gbl.F.Out,"%u/%u",Match->Status.QstInd,NumQsts);
       HTM_DIV_End ();
      }
@@ -1351,7 +1350,7 @@ void Mch_ResumeMatch (void)
    Mch_UpdateMatchStatusInDB (&Match);
 
    /***** Show current match status *****/
-   fprintf (Gbl.F.Out,"<div id=\"match\" class=\"MCH_CONT\">");
+   HTM_DIV_Begin ("id=\"match\" class=\"MCH_CONT\"");
    Mch_ShowMatchStatusForTch (&Match);
    HTM_DIV_End ();
   }
@@ -1784,7 +1783,7 @@ void Mch_PlayPauseMatch (void)
    Mch_UpdateMatchStatusInDB (&Match);
 
    /***** Show current match status *****/
-   fprintf (Gbl.F.Out,"<div id=\"match\" class=\"MCH_CONT\">");
+   HTM_DIV_Begin ("id=\"match\" class=\"MCH_CONT\"");
    Mch_ShowMatchStatusForTch (&Match);
    HTM_DIV_End ();
   }
@@ -1817,7 +1816,7 @@ void Mch_ChangeNumColsMch (void)
    Mch_UpdateMatchStatusInDB (&Match);
 
    /***** Show current match status *****/
-   fprintf (Gbl.F.Out,"<div id=\"match\" class=\"MCH_CONT\">");
+   HTM_DIV_Begin ("id=\"match\" class=\"MCH_CONT\"");
    Mch_ShowMatchStatusForTch (&Match);
    HTM_DIV_End ();
   }
@@ -1849,7 +1848,7 @@ void Mch_ToggleVisibilResultsMchQst (void)
    Mch_UpdateMatchStatusInDB (&Match);
 
    /***** Show current match status *****/
-   fprintf (Gbl.F.Out,"<div id=\"match\" class=\"MCH_CONT\">");
+   HTM_DIV_Begin ("id=\"match\" class=\"MCH_CONT\"");
    Mch_ShowMatchStatusForTch (&Match);
    HTM_DIV_End ();
   }
@@ -1878,7 +1877,7 @@ void Mch_BackMatch (void)
    Mch_UpdateMatchStatusInDB (&Match);
 
    /***** Show current match status *****/
-   fprintf (Gbl.F.Out,"<div id=\"match\" class=\"MCH_CONT\">");
+   HTM_DIV_Begin ("id=\"match\" class=\"MCH_CONT\"");
    Mch_ShowMatchStatusForTch (&Match);
    HTM_DIV_End ();
   }
@@ -1907,7 +1906,7 @@ void Mch_ForwardMatch (void)
    Mch_UpdateMatchStatusInDB (&Match);
 
    /***** Show current match status *****/
-   fprintf (Gbl.F.Out,"<div id=\"match\" class=\"MCH_CONT\">");
+   HTM_DIV_Begin ("id=\"match\" class=\"MCH_CONT\"");
    Mch_ShowMatchStatusForTch (&Match);
    HTM_DIV_End ();
   }
@@ -2110,11 +2109,10 @@ bool Mch_CheckIfICanPlayThisMatchBasedOnGrps (long MchCod)
 static void Mch_ShowLeftColumnTch (struct Match *Match)
   {
    /***** Start left container *****/
-   fprintf (Gbl.F.Out,"<div class=\"MCH_LEFT\">");
+   HTM_DIV_Begin ("class=\"MCH_LEFT\"");
 
    /***** Refreshable part *****/
-   fprintf (Gbl.F.Out,"<div id=\"match_left\""
-	              " class=\"MCH_REFRESHABLE_TEACHER\">");
+   HTM_DIV_Begin ("id=\"match_left\" class=\"MCH_REFRESHABLE_TEACHER\"");
    Mch_ShowRefreshablePartTch (Match);
    HTM_DIV_End ();
 
@@ -2142,7 +2140,7 @@ static void Mch_ShowRefreshablePartTch (struct Match *Match)
    unsigned NumAnswerersQst;
 
    /***** Top *****/
-   fprintf (Gbl.F.Out,"<div class=\"MCH_TOP\">");
+   HTM_DIV_Begin ("class=\"MCH_TOP\"");
 
    /* Write elapsed time in match */
    Mch_GetElapsedTimeInMatch (Match,&Time);
@@ -2154,7 +2152,7 @@ static void Mch_ShowRefreshablePartTch (struct Match *Match)
    Mch_ShowNumQstInMatch (Match);
 
    /***** Write elapsed time in question *****/
-   fprintf (Gbl.F.Out,"<div class=\"MCH_TIME_QST\">");
+   HTM_DIV_Begin ("class=\"MCH_TIME_QST\"");
    if (Match->Status.QstInd > 0 &&
        Match->Status.QstInd < Mch_AFTER_LAST_QUESTION)
      {
@@ -2168,7 +2166,7 @@ static void Mch_ShowRefreshablePartTch (struct Match *Match)
    /***** Number of users who have answered this question *****/
    NumAnswerersQst = Mch_GetNumUsrsWhoHaveAnswerQst (Match->MchCod,
 						     Match->Status.QstInd);
-   fprintf (Gbl.F.Out,"<div class=\"MCH_NUM_ANSWERERS\">");
+   HTM_DIV_Begin ("class=\"MCH_NUM_ANSWERERS\"");
    fprintf (Gbl.F.Out,"%s<br />"
 		      "<strong>",
 	    Txt_MATCH_respond);
@@ -2197,7 +2195,7 @@ static void Mch_ShowRefreshablePartTch (struct Match *Match)
 static void Mch_ShowRightColumnTch (struct Match *Match)
   {
    /***** Start right container *****/
-   fprintf (Gbl.F.Out,"<div class=\"MCH_RIGHT\">");
+   HTM_DIV_Begin ("class=\"MCH_RIGHT\"");
 
    /***** Top row: match title *****/
    Mch_ShowMatchTitle (Match);
@@ -2219,10 +2217,10 @@ static void Mch_ShowRightColumnTch (struct Match *Match)
 static void Mch_ShowLeftColumnStd (struct Match *Match)
   {
    /***** Start left container *****/
-   fprintf (Gbl.F.Out,"<div class=\"MCH_LEFT\">");
+   HTM_DIV_Begin ("class=\"MCH_LEFT\"");
 
    /***** Top *****/
-   fprintf (Gbl.F.Out,"<div class=\"MCH_TOP\">");
+   HTM_DIV_Begin ("class=\"MCH_TOP\"");
    HTM_DIV_End ();
 
    /***** Write number of question *****/
@@ -2241,7 +2239,7 @@ static void Mch_ShowRightColumnStd (struct Match *Match)
    extern const char *Txt_Please_wait_;
 
    /***** Start right container *****/
-   fprintf (Gbl.F.Out,"<div class=\"MCH_RIGHT\">");
+   HTM_DIV_Begin ("class=\"MCH_RIGHT\"");
 
    /***** Top row *****/
    Mch_ShowMatchTitle (Match);
@@ -2251,7 +2249,7 @@ static void Mch_ShowRightColumnStd (struct Match *Match)
      {
       if (Match->Status.QstInd < Mch_AFTER_LAST_QUESTION)	// Unfinished
 	{
-	 fprintf (Gbl.F.Out,"<div class=\"MCH_BOTTOM\">");
+	 HTM_DIV_Begin ("class=\"MCH_BOTTOM\"");
 
 	 /***** Update players ******/
 	 Mch_RegisterMeAsPlayerInMatch (Match->MchCod);
@@ -2279,7 +2277,7 @@ static void Mch_ShowNumQstInMatch (struct Match *Match)
    extern const char *Txt_MATCH_End;
    unsigned NumQsts = Gam_GetNumQstsGame (Match->GamCod);
 
-   fprintf (Gbl.F.Out,"<div class=\"MCH_NUM_QST\">");
+   HTM_DIV_Begin ("class=\"MCH_NUM_QST\"");
    if (Match->Status.QstInd == 0)				// Not started
       fprintf (Gbl.F.Out,"%s",Txt_MATCH_Start);
    else if (Match->Status.QstInd >= Mch_AFTER_LAST_QUESTION)	// Finished
@@ -2302,10 +2300,10 @@ static void Mch_PutMatchControlButtons (struct Match *Match)
    extern const char *Txt_Resume;
 
    /***** Start buttons container *****/
-   fprintf (Gbl.F.Out,"<div class=\"MCH_BUTTONS_CONTAINER\">");
+   HTM_DIV_Begin ("class=\"MCH_BUTTONS_CONTAINER\"");
 
    /***** Left button *****/
-   fprintf (Gbl.F.Out,"<div class=\"MCH_BUTTON_LEFT_CONTAINER\">");
+   HTM_DIV_Begin ("class=\"MCH_BUTTON_LEFT_CONTAINER\"");
    if (Match->Status.QstInd == 0)
       /* Put button to close browser tab */
       Mch_PutBigButtonClose ();
@@ -2316,7 +2314,7 @@ static void Mch_PutMatchControlButtons (struct Match *Match)
    HTM_DIV_End ();
 
    /***** Center button *****/
-   fprintf (Gbl.F.Out,"<div class=\"MCH_BUTTON_CENTER_CONTAINER\">");
+   HTM_DIV_Begin ("class=\"MCH_BUTTON_CENTER_CONTAINER\"");
    if (Match->Status.Playing)					// Being played
       /* Put button to pause match */
       Mch_PutBigButton (ActPlyPauMch,"play_pause",Match->MchCod,
@@ -2335,7 +2333,7 @@ static void Mch_PutMatchControlButtons (struct Match *Match)
    HTM_DIV_End ();
 
    /***** Right button *****/
-   fprintf (Gbl.F.Out,"<div class=\"MCH_BUTTON_RIGHT_CONTAINER\">");
+   HTM_DIV_Begin ("class=\"MCH_BUTTON_RIGHT_CONTAINER\"");
    if (Match->Status.QstInd >= Mch_AFTER_LAST_QUESTION)	// Finished
       /* Put button to close browser tab */
       Mch_PutBigButtonClose ();
@@ -2374,9 +2372,10 @@ static void Mch_ShowFormColumns (struct Match *Match)
 	NumCols <= Mch_MAX_COLS;
 	NumCols++)
      {
-      fprintf (Gbl.F.Out,"<div class=\"%s\">",
-	       (Match->Status.NumCols == NumCols) ? "PREF_ON" :
-					            "PREF_OFF");
+      HTM_DIV_Begin ("class=\"%s\"",
+		     (Match->Status.NumCols == NumCols) ? "PREF_ON" :
+							  "PREF_OFF");
+
       /***** Begin form *****/
       Frm_StartForm (ActChgNumColMch);
       Mch_PutParamMchCod (Match->MchCod);	// Current match being played
@@ -2417,9 +2416,8 @@ static void Mch_ShowFormViewResult (struct Match *Match)
 
    /***** Begin selector *****/
    Set_StartOneSettingSelector ();
-   fprintf (Gbl.F.Out,"<div class=\"%s\">",
-	    (Match->Status.ShowQstResults) ? "PREF_ON" :
-					     "PREF_OFF");
+   HTM_DIV_Begin ("class=\"%s\"",(Match->Status.ShowQstResults) ? "PREF_ON" :
+					                          "PREF_OFF");
 
    /***** Begin form *****/
    Frm_StartForm (ActChgVisResMchQst);
@@ -2442,7 +2440,7 @@ static void Mch_ShowFormViewResult (struct Match *Match)
 static void Mch_ShowMatchTitle (struct Match *Match)
   {
    /***** Match title *****/
-   fprintf (Gbl.F.Out,"<div class=\"MCH_TOP\">");
+   HTM_DIV_Begin ("class=\"MCH_TOP\"");
    fprintf (Gbl.F.Out,"%s",Match->Title);
    HTM_DIV_End ();
   }
@@ -2480,7 +2478,7 @@ static void Mch_ShowQuestionAndAnswersTch (struct Match *Match)
    if (Gbl.Test.AnswerType != Tst_ANS_UNIQUE_CHOICE)
       Lay_ShowErrorAndExit ("Wrong answer type.");
 
-   fprintf (Gbl.F.Out,"<div class=\"MCH_BOTTOM\">");	// Bottom
+   HTM_DIV_Begin ("class=\"MCH_BOTTOM\"");	// Bottom
 
    /* Write stem (row[1]) */
    Tst_WriteQstStem (row[1],"MCH_TCH_STEM");
@@ -2868,7 +2866,7 @@ static void Mch_PutBigButton (Act_Action_t NextAction,const char *Id,
    Mch_PutParamMchCod (MchCod);
 
    /***** Put icon with link *****/
-   fprintf (Gbl.F.Out,"<div class=\"MCH_BUTTON_CONTAINER\">");
+   HTM_DIV_Begin ("class=\"MCH_BUTTON_CONTAINER\"");
    fprintf (Gbl.F.Out,"<a href=\"\" class=\"MCH_BUTTON_ON\" title=\"%s\" "
 	              " onclick=\"document.getElementById('%s').submit();"
 	              " return false;\">"
@@ -2886,8 +2884,8 @@ static void Mch_PutBigButton (Act_Action_t NextAction,const char *Id,
 static void Mch_PutBigButtonOff (const char *Icon)
   {
    /***** Put inactive icon *****/
-   fprintf (Gbl.F.Out,"<div class=\"MCH_BUTTON_CONTAINER\">");
-   fprintf (Gbl.F.Out,"<div class=\"MCH_BUTTON_OFF\">");
+   HTM_DIV_Begin ("class=\"MCH_BUTTON_CONTAINER\"");
+   HTM_DIV_Begin ("class=\"MCH_BUTTON_OFF\"");
    fprintf (Gbl.F.Out,"<i class=\"%s\"></i>",Icon);
    HTM_DIV_End ();
    HTM_DIV_End ();
@@ -2898,7 +2896,7 @@ static void Mch_PutBigButtonClose (void)
    extern const char *Txt_Close;
 
    /***** Put icon with link *****/
-   fprintf (Gbl.F.Out,"<div class=\"MCH_BUTTON_CONTAINER\">");
+   HTM_DIV_Begin ("class=\"MCH_BUTTON_CONTAINER\"");
    fprintf (Gbl.F.Out,"<a href=\"\" class=\"MCH_BUTTON_ON\" title=\"%s\" "
 	              " onclick=\"window.close();"
 	              " return false;\"\">"
@@ -2914,7 +2912,7 @@ static void Mch_PutBigButtonClose (void)
 
 static void Mch_ShowWaitImage (const char *Txt)
   {
-   fprintf (Gbl.F.Out,"<div class=\"MCH_WAIT_CONTAINER\">");
+   HTM_DIV_Begin ("class=\"MCH_WAIT_CONTAINER\"");
    fprintf (Gbl.F.Out,"<img src=\"%s/wait.gif\""
 		      " alt=\"%s\" title=\"%s\" class=\"MCH_WAIT_IMG\" />",
 	    Cfg_URL_ICON_PUBLIC,
@@ -3017,7 +3015,7 @@ void Mch_JoinMatchAsStd (void)
    Mch_GetDataOfMatchByCod (&Match);
 
    /***** Show current match status *****/
-   fprintf (Gbl.F.Out,"<div id=\"match\" class=\"MCH_CONT\">");
+   HTM_DIV_Begin ("id=\"match\" class=\"MCH_CONT\"");
    Mch_ShowMatchStatusForStd (&Match);
    HTM_DIV_End ();
   }
@@ -3222,7 +3220,7 @@ void Mch_ReceiveQuestionAnswer (void)
      }
 
    /***** Show current match status *****/
-   fprintf (Gbl.F.Out,"<div id=\"match\" class=\"MCH_CONT\">");
+   HTM_DIV_Begin ("id=\"match\" class=\"MCH_CONT\"");
    Mch_ShowMatchStatusForStd (&Match);
    HTM_DIV_End ();
   }
@@ -3350,7 +3348,7 @@ static void Mch_DrawBarNumUsrs (unsigned NumAnswerersAns,unsigned NumAnswerersQs
                 Txt_of_PART_OF_A_TOTAL,NumAnswerersQst);
 
    /***** Start container *****/
-   fprintf (Gbl.F.Out,"<div class=\"MCH_RESULT\">");
+   HTM_DIV_Begin ("class=\"MCH_RESULT\"");
 
    /***** Draw bar with a with proportional to the number of clicks *****/
    if (NumAnswerersAns && NumAnswerersQst)
diff --git a/swad_match_result.c b/swad_match_result.c
index b740d785..6d5ca372 100644
--- a/swad_match_result.c
+++ b/swad_match_result.c
@@ -93,7 +93,7 @@ void McR_PutFormToViewMchResults (Act_Action_t Action)
   {
    extern const char *Txt_Results;
 
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
    Lay_PutContextualLinkIconText (Action,NULL,NULL,
 				  "tasks.svg",
 				  Txt_Results);
diff --git a/swad_media.c b/swad_media.c
index af56d164..f69ef047 100644
--- a/swad_media.c
+++ b/swad_media.c
@@ -351,10 +351,10 @@ void Med_PutMediaUploader (int NumMediaInForm,const char *ClassInput)
    Frm_SetUniqueId (Id);
 
    /***** Start media uploader container *****/
-   fprintf (Gbl.F.Out,"<div class=\"MED_UPLOADER\">");		// container
+   HTM_DIV_Begin ("class=\"MED_UPLOADER\"");		// container
 
    /***** Icon 'clip' *****/
-   fprintf (Gbl.F.Out,"<div id=\"%s_med_ico\">",Id);		// <id>_med_ico
+   HTM_DIV_Begin ("id=\"%s_med_ico\"",Id);		// <id>_med_ico
    fprintf (Gbl.F.Out,"<a href=\"\""
                       " onclick=\"mediaActivateMediaUploader('%s');return false;\">"
 		      "<img src=\"%s/paperclip.svg\""
@@ -367,9 +367,8 @@ void Med_PutMediaUploader (int NumMediaInForm,const char *ClassInput)
    HTM_DIV_End ();						// <id>_med_ico
 
    /***** Start media uploader *****/
-   fprintf (Gbl.F.Out,"<div id=\"%s_med_upl\""			// container <id>_med_upl
-	              " style=\"display:none;\" />",
-            Id);
+   HTM_DIV_Begin ("id=\"%s_med_upl\" style=\"display:none;\"",	// container <id>_med_upl
+		  Id);
 
    /***** Start box *****/
    Box_StartBox (NULL,Txt_Multimedia,NULL,
@@ -380,8 +379,8 @@ void Med_PutMediaUploader (int NumMediaInForm,const char *ClassInput)
 
    /***** Icons *****/
    /* Start icons */
-   fprintf (Gbl.F.Out,"<div class=\"PREF_CONTAINERS\">");	// icons containers
-   fprintf (Gbl.F.Out,"<div class=\"PREF_CONTAINER\">");	// icons container
+   HTM_DIV_Begin ("class=\"PREF_CONTAINERS\"");			// icons containers
+   HTM_DIV_Begin ("class=\"PREF_CONTAINER\"");			// icons container
 
    /* Upload icon */
    Med_PutIconMediaUploader (Id,"ico_upl",			// <id>_ico_upl
@@ -475,7 +474,7 @@ static void Med_PutIconMediaUploader (const char UniqueId[Frm_MAX_BYTES_ID + 1],
 				      const char *Title)
   {
    /***** Icon to activate form in media uploader *****/
-   fprintf (Gbl.F.Out,"<div id=\"%s_%s\" class=\"PREF_OFF\">",	// <id>_IdSuffix
+   HTM_DIV_Begin ("id=\"%s_%s\" class=\"PREF_OFF\"",		// <id>_IdSuffix
             UniqueId,IdSuffix);
    fprintf (Gbl.F.Out,"<a href=\"\" onclick=\"%s('%s');return false;\">"
                       "<img src=\"%s/%s\" alt=\"%s\" title=\"%s\""
@@ -1442,7 +1441,7 @@ void Med_ShowMedia (struct Media *Media,
       return;
 
    /***** Start media container *****/
-   fprintf (Gbl.F.Out,"<div class=\"%s\">",ClassContainer);
+   HTM_DIV_Begin ("class=\"%s\"",ClassContainer);
 
    switch (Media->Type)
      {
@@ -1622,11 +1621,11 @@ static void Med_ShowGIF (struct Media *Media,
 		   FileNameMedia);
 
 	 /***** Show static PNG and animated GIF *****/
-	 fprintf (Gbl.F.Out,"<div class=\"MED_PLAY\""
-			    " onmouseover=\"toggleOnGIF(this,'%s');\""
-			    " onmouseout=\"toggleOffGIF(this,'%s');\">",
-		  URL_GIF,
-		  URL_PNG);
+	 HTM_DIV_Begin ("class=\"MED_PLAY\""
+			" onmouseover=\"toggleOnGIF(this,'%s');\""
+			" onmouseout=\"toggleOffGIF(this,'%s');\"",
+			URL_GIF,
+			URL_PNG);
 
 	 /* Image */
 	 fprintf (Gbl.F.Out,"<img src=\"%s\" class=\"%s\" alt=\"\"",
@@ -1723,7 +1722,7 @@ static void Med_ShowYoutube (struct Media *Media,const char *ClassMedia)
 	 // 	allow="accelerometer; autoplay; encrypted-media;
 	 // 	gyroscope; picture-in-picture" allowfullscreen>
 	 // </iframe>
-	 fprintf (Gbl.F.Out,"<div class=\"MED_VIDEO_CONT\">");
+	 HTM_DIV_Begin ("class=\"MED_VIDEO_CONT\"");
 	 fprintf (Gbl.F.Out,"<iframe src=\"https://www.youtube.com/embed/%s\""
 			    " frameborder=\"0\""
 			    " allow=\"accelerometer; autoplay; encrypted-media;"
@@ -1763,7 +1762,7 @@ static void Med_ShowEmbed (struct Media *Media,const char *ClassMedia)
 	 // 	style="border:1px solid #CCC; border-width:1px; margin-bottom:5px; max-width: 100%;"
 	 // 	allowfullscreen>
 	 // </iframe>
-	 fprintf (Gbl.F.Out,"<div class=\"MED_EMBED_CONT\">");
+	 HTM_DIV_Begin ("class=\"MED_EMBED_CONT\"");
 	 fprintf (Gbl.F.Out,"<iframe src=\"%s\""
 			    " frameborder=\"0\""
 	 	            " marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\""
diff --git a/swad_menu.c b/swad_menu.c
index 4bf9b29a..9db0755f 100644
--- a/swad_menu.c
+++ b/swad_menu.c
@@ -360,23 +360,21 @@ void Mnu_WriteMenuThisTab (void)
 	 fprintf (Gbl.F.Out,"<li class=\"MENU_LIST_ITEM\">");
 
          /***** Start container used to highlight this option *****/
-         fprintf (Gbl.F.Out,"<div class=\"%s\">",
-                  IsTheSelectedAction ? "MENU_OPT_ON" :
-                	                "MENU_OPT_OFF");
+         HTM_DIV_Begin ("class=\"%s\"",
+			IsTheSelectedAction ? "MENU_OPT_ON" :
+					      "MENU_OPT_OFF");
 
          /***** Begin form and link *****/
          Frm_StartForm (NumAct);
          Frm_LinkFormSubmit (Title,The_ClassTxtMenu[Gbl.Prefs.Theme],NULL);
 
          /***** Icon *****/
-	 fprintf (Gbl.F.Out,"<div class=\"MENU_ICO\""
-			    " style=\"background-image:url('%s/%s');\">",
-	          Gbl.Prefs.URLIconSet,
-		  Act_GetIcon (NumAct));
+	 HTM_DIV_Begin ("class=\"MENU_ICO\" style=\"background-image:url('%s/%s');\"",
+			Gbl.Prefs.URLIconSet,
+			Act_GetIcon (NumAct));
 
          /***** Text *****/
-	 fprintf (Gbl.F.Out,"<div class=\"MENU_TEXT %s\">",
-		  The_ClassTxtMenu[Gbl.Prefs.Theme]);
+	 HTM_DIV_Begin ("class=\"MENU_TEXT %s\"",The_ClassTxtMenu[Gbl.Prefs.Theme]);
 	 fprintf (Gbl.F.Out,"%s",Txt_MENU_TITLE[Gbl.Action.Tab][NumOptInMenu]);
 	 HTM_DIV_End ();
 
@@ -417,9 +415,8 @@ void Mnu_PutIconsToSelectMenu (void)
 	Menu < Mnu_NUM_MENUS;
 	Menu++)
      {
-      fprintf (Gbl.F.Out,"<div class=\"%s\">",
-               Menu == Gbl.Prefs.Menu ? "PREF_ON" :
-        	                        "PREF_OFF");
+      HTM_DIV_Begin ("class=\"%s\"",Menu == Gbl.Prefs.Menu ? "PREF_ON" :
+        	                                             "PREF_OFF");
       Frm_StartForm (ActChgMnu);
       Par_PutHiddenParamUnsigned ("Menu",(unsigned) Menu);
       Ico_PutSettingIconLink (Mnu_MenuIcons[Menu],Txt_MENU_NAMES[Menu]);
diff --git a/swad_message.c b/swad_message.c
index cb89a593..f82a3179 100644
--- a/swad_message.c
+++ b/swad_message.c
@@ -364,7 +364,7 @@ static void Msg_PutLinkToShowMorePotentialRecipients (void)
   {
    extern const char *Txt_Show_more_recipients;
 
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
    Lay_PutContextualLinkIconTextOnSubmit (ActReqMsgUsr,NULL,
 					  Msg_PutParamsShowMorePotentialRecipients,
 					  "users.svg",
@@ -442,16 +442,16 @@ static void Msg_ShowOneUniqueRecipient (void)
 		     "PHOTO21x28",Pho_ZOOM,false);
 
    /****** Write user's IDs ******/
-   fprintf (Gbl.F.Out,"<div class=\"MSG_TO_ONE_RCP %s\">",
-            Gbl.Usrs.Other.UsrDat.Accepted ? "DAT_SMALL_NOBR_N" :
-        	                             "DAT_SMALL_NOBR");
+   HTM_DIV_Begin ("class=\"MSG_TO_ONE_RCP %s\"",
+		  Gbl.Usrs.Other.UsrDat.Accepted ? "DAT_SMALL_NOBR_N" :
+						   "DAT_SMALL_NOBR");
    ID_WriteUsrIDs (&Gbl.Usrs.Other.UsrDat,NULL);
    HTM_DIV_End ();
 
    /***** Write user's name *****/
-   fprintf (Gbl.F.Out,"<div class=\"MSG_TO_ONE_RCP %s\">",
-            Gbl.Usrs.Other.UsrDat.Accepted ? "DAT_SMALL_NOBR_N" :
-        	                             "DAT_SMALL_NOBR");
+   HTM_DIV_Begin ("class=\"MSG_TO_ONE_RCP %s\"",
+		  Gbl.Usrs.Other.UsrDat.Accepted ? "DAT_SMALL_NOBR_N" :
+						   "DAT_SMALL_NOBR");
    fprintf (Gbl.F.Out,"%s",Gbl.Usrs.Other.UsrDat.FullName);
    HTM_DIV_End ();
 
@@ -1665,7 +1665,7 @@ void Msg_ShowRecMsgs (void)
    /***** Link to view banned users *****/
    if (Msg_GetNumUsrsBannedByMe ())
      {
-      fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+      HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
       Msg_PutLinkToViewBannedUsers ();
       HTM_DIV_End ();
      }
@@ -1759,14 +1759,14 @@ static void Msg_ShowSentOrReceivedMessages (void)
    /* Form to see messages again */
    Frm_StartForm (ActionSee[Gbl.Msg.TypeOfMessages]);
 
-   fprintf (Gbl.F.Out,"<div class=\"CM\">");
+   HTM_DIV_Begin ("class=\"CM\"");
    Msg_ShowFormSelectCourseSentOrRecMsgs ();
    if (Gbl.Msg.TypeOfMessages == Msg_MESSAGES_RECEIVED)
       Msg_ShowFormToShowOnlyUnreadMessages ();
    HTM_DIV_End ();
    Msg_ShowFormToFilterMsgs ();
 
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
    Frm_LinkFormSubmitAnimated (Txt_Update_messages,
 	                       The_ClassFormInBoxBold[Gbl.Prefs.Theme],
 			       NULL);
@@ -3229,7 +3229,7 @@ void Msg_WriteMsgAuthor (struct UsrData *UsrDat,bool Enabled,const char *BgColor
 	 HTM_TD_Begin ("class=\"LT %s\"",BgColor);
       else
 	 HTM_TD_Begin ("class=\"LT\"");
-      fprintf (Gbl.F.Out,"<div class=\"AUTHOR_2_LINES\">");	// Limited width
+      HTM_DIV_Begin ("class=\"AUTHOR_2_LINES\"");	// Limited width
       Usr_WriteFirstNameBRSurnames (UsrDat);
       HTM_DIV_End ();
      }
@@ -3282,7 +3282,7 @@ bool Msg_WriteCrsOrgMsg (long CrsCod)
          ThereIsOrgCrs = true;
          if ((FromThisCrs = (CrsCod == Gbl.Hierarchy.Crs.CrsCod)))	// Message sent from current course
            {
-            fprintf (Gbl.F.Out,"<div class=\"AUTHOR_TXT\">");
+            HTM_DIV_Begin ("class=\"AUTHOR_TXT\"");
             fprintf (Gbl.F.Out,"(%s)",Txt_from_this_course);
             HTM_DIV_End ();
            }
@@ -3291,7 +3291,7 @@ bool Msg_WriteCrsOrgMsg (long CrsCod)
             /* Write course, including link */
             Frm_StartFormGoTo (ActSeeCrsInf);
             Crs_PutParamCrsCod (Crs.CrsCod);
-            fprintf (Gbl.F.Out,"<div class=\"AUTHOR_TXT\">");
+            HTM_DIV_Begin ("class=\"AUTHOR_TXT\"");
             fprintf (Gbl.F.Out,"(");
             snprintf (Gbl.Title,sizeof (Gbl.Title),
         	      Txt_Go_to_X,
@@ -3306,7 +3306,7 @@ bool Msg_WriteCrsOrgMsg (long CrsCod)
      }
    if (!ThereIsOrgCrs)	// It's an old message without origin source specified, or is a message sent from none course
      {
-      fprintf (Gbl.F.Out,"<div class=\"AUTHOR_TXT\">");
+      HTM_DIV_Begin ("class=\"AUTHOR_TXT\"");
       fprintf (Gbl.F.Out,"(%s)",Txt_no_course_of_origin);
       HTM_DIV_End ();
      }
diff --git a/swad_network.c b/swad_network.c
index 82ecafa5..db8d872f 100644
--- a/swad_network.c
+++ b/swad_network.c
@@ -207,7 +207,7 @@ void Net_ShowWebsAndSocialNets (const struct UsrData *UsrDat)
    char URL[Cns_MAX_BYTES_WWW + 1];
 
    /***** Start container *****/
-   fprintf (Gbl.F.Out,"<div class=\"REC_WEBS\">");
+   HTM_DIV_Begin ("class=\"REC_WEBS\"");
 
    /***** Show link to public profile *****/
    Net_ShowAWebOrSocialNet (Prf_GetURLPublicProfile (URL,UsrDat->Nickname),
@@ -251,7 +251,7 @@ static void Net_ShowAWebOrSocialNet (const char *URL,
                                      const char *Icon,const char *Title)
   {
    /***** Write link and icon *****/
-   fprintf (Gbl.F.Out,"<div class=\"ICO_HIGHLIGHT\" style=\"display:inline;\">");
+   HTM_DIV_Begin ("class=\"ICO_HIGHLIGHT\" style=\"display:inline;\"");
    fprintf (Gbl.F.Out,"<a href=\"%s\" target=\"_blank\" title=\"%s\">"
 		      "<img src=\"%s/%s\""
 		      " alt=\"%s\" title=\"%s\""
diff --git a/swad_notice.c b/swad_notice.c
index e6f4a2ca..8d14f74b 100644
--- a/swad_notice.c
+++ b/swad_notice.c
@@ -469,7 +469,7 @@ void Not_ShowNotices (Not_Listing_t TypeNoticesListing,long HighlightNotCod)
 	    RSS_UpdateRSSFileForACrs (&Gbl.Hierarchy.Crs);
 
 	 /* Put a link to the RSS file */
-	 fprintf (Gbl.F.Out,"<div class=\"CM\">");
+	 HTM_DIV_Begin ("class=\"CM\"");
 	 fprintf (Gbl.F.Out,"<a href=\"");
 	 RSS_WriteRSSLink (Gbl.F.Out,Gbl.Hierarchy.Crs.CrsCod);
 	 fprintf (Gbl.F.Out,"\" target=\"_blank\">"
@@ -654,12 +654,12 @@ static void Not_DrawANotice (Not_Listing_t TypeNoticesListing,
      {
       Lay_StartArticle (Anchor);
       if (Highlight)
-	 fprintf (Gbl.F.Out,"<div class=\"NOTICE_HIGHLIGHT\">");
+	 HTM_DIV_Begin ("class=\"NOTICE_HIGHLIGHT\"");
      }
 
    /***** Start yellow note *****/
-   fprintf (Gbl.F.Out,"<div class=\"%s %s\">",
-	    ContainerClass[Status],ContainerWidthClass[TypeNoticesListing]);
+   HTM_DIV_Begin ("class=\"%s %s\"",
+	          ContainerClass[Status],ContainerWidthClass[TypeNoticesListing]);
 
    /***** Write the date in the top part of the yellow note *****/
    /* Write symbol to indicate if notice is obsolete or active */
@@ -686,7 +686,7 @@ static void Not_DrawANotice (Not_Listing_t TypeNoticesListing,
 
    /* Write the date */
    UniqueId++;
-   fprintf (Gbl.F.Out,"<div class=\"%s\">",DateClass[Status]);
+   HTM_DIV_Begin ("class=\"%s\"",DateClass[Status]);
    if (TypeNoticesListing == Not_LIST_BRIEF_NOTICES)
      {
       /* Form to view full notice */
@@ -712,12 +712,12 @@ static void Not_DrawANotice (Not_Listing_t TypeNoticesListing,
    /***** Write the content of the notice *****/
    if (TypeNoticesListing == Not_LIST_BRIEF_NOTICES)
      {
-      fprintf (Gbl.F.Out,"<div class=\"NOTICE_TEXT_BRIEF\">");
+      HTM_DIV_Begin ("class=\"NOTICE_TEXT_BRIEF\"");
       fprintf (Gbl.F.Out,"%s",Content);
       HTM_DIV_End ();
 
       /* Put form to view full notice */
-      fprintf (Gbl.F.Out,"<div class=\"CM\">");
+      HTM_DIV_Begin ("class=\"CM\"");
       Not_SetNotCodToEdit (NotCod);	// To be used as parameter
       Lay_PutContextualLinkOnlyIcon (ActSeeOneNot,Anchor,Not_PutParams,
 				     "ellipsis-h.svg",
@@ -726,14 +726,14 @@ static void Not_DrawANotice (Not_Listing_t TypeNoticesListing,
      }
    else
      {
-      fprintf (Gbl.F.Out,"<div class=\"%s\">",TextClass[Status]);
+      HTM_DIV_Begin ("class=\"%s\"",TextClass[Status]);
       fprintf (Gbl.F.Out,"%s",Content);
       HTM_DIV_End ();
      }
 
    /***** Write the author *****/
-   fprintf (Gbl.F.Out,"<div class=\"NOTICE_AUTHOR %s\">",	// Limited width
-            AuthorClass[Status]);
+   HTM_DIV_Begin ("class=\"NOTICE_AUTHOR %s\"",	// Limited width
+                  AuthorClass[Status]);
    Usr_UsrDataConstructor (&UsrDat);
    UsrDat.UsrCod = UsrCod;
    if (Usr_ChkUsrCodAndGetAllUsrDataFromUsrCod (&UsrDat,Usr_DONT_GET_PREFS)) // Get from the database the data of the autor
diff --git a/swad_notification.c b/swad_notification.c
index 8582df36..80835daa 100644
--- a/swad_notification.c
+++ b/swad_notification.c
@@ -359,7 +359,7 @@ void Ntf_ShowMyNotifications (void)
 				      Gbl.Usrs.Me.UsrDat.UsrCod,SubQuery);
 
    /***** Contextual links *****/
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 
    /* Write form to show all notifications */
    Ntf_WriteFormAllNotifications (AllNotifications);
diff --git a/swad_pagination.c b/swad_pagination.c
index 02a75c46..4a8ab85c 100644
--- a/swad_pagination.c
+++ b/swad_pagination.c
@@ -128,7 +128,7 @@ void Pag_WriteLinksToPagesCentered (Pag_WhatPaginate_t WhatPaginate,
                                     long ThrCod,
                                     struct Pagination *Pagination)
   {
-   fprintf (Gbl.F.Out,"<div class=\"CM\">");
+   HTM_DIV_Begin ("class=\"CM\"");
    Pag_WriteLinksToPages (WhatPaginate,
                           ThrCod,
                           Pagination,true,NULL,"PAG_TXT",false);
diff --git a/swad_password.c b/swad_password.c
index 175dacca..faaad82b 100644
--- a/swad_password.c
+++ b/swad_password.c
@@ -888,7 +888,7 @@ void Pwd_AskForConfirmationOnDangerousAction (void)
    extern const char *Txt_I_understand_that_this_action_can_not_be_undone;
    extern const char *Txt_For_security_enter_your_password;
 
-   fprintf (Gbl.F.Out,"<div class=\"CM\" style=\"margin:12px;\">");
+   HTM_DIV_Begin ("class=\"CM\" style=\"margin:12px;\"");
    fprintf (Gbl.F.Out,"<label class=\"%s\">"
 		      "<input type=\"checkbox\" name=\"Consent\" value=\"Y\" />"
 		      "%s"
diff --git a/swad_photo.c b/swad_photo.c
index 0192f3a5..f602758a 100644
--- a/swad_photo.c
+++ b/swad_photo.c
@@ -784,7 +784,7 @@ static bool Pho_ReceivePhotoAndDetectFaces (bool ItsMe,const struct UsrData *Usr
 	     "%s/%s_map.jpg",
              Cfg_PATH_PHOTO_TMP_PUBLIC,
 	     Gbl.UniqueNameEncrypted);
-   fprintf (Gbl.F.Out,"<div class=\"TIT CM\">");
+   HTM_DIV_Begin ("class=\"TIT CM\"");
    fprintf (Gbl.F.Out,"<img src=\"%s/%s_map.jpg\""
                       " usemap=\"#faces_map\""
                       " alt=\"%s\" title=\"%s\" />",
@@ -1207,18 +1207,17 @@ void Pho_ShowUsrPhoto (const struct UsrData *UsrDat,const char *PhotoURL,
    if (PutZoomCode)
      {
       Frm_SetUniqueId (IdCaption);
-      fprintf (Gbl.F.Out,"<div id=\"%s\" class=\"NOT_SHOWN\">",
-      	       IdCaption);
+      HTM_DIV_Begin ("id=\"%s\" class=\"NOT_SHOWN\"",IdCaption);
 
       /* First name and surnames */
-      fprintf (Gbl.F.Out,"<div class=\"ZOOM_TXT_LINE DAT_N_BOLD\">");	// Limited width
+      HTM_DIV_Begin ("class=\"ZOOM_TXT_LINE DAT_N_BOLD\"");	// Limited width
       Usr_WriteFirstNameBRSurnames (UsrDat);
       HTM_DIV_End ();
 
       /* Nickname */
       if (UsrDat->Nickname[0])
 	{
-	 fprintf (Gbl.F.Out,"<div class=\"ZOOM_TXT_LINE DAT_SMALL_N\">");
+	 HTM_DIV_Begin ("class=\"ZOOM_TXT_LINE DAT_SMALL_N\"");
 	 fprintf (Gbl.F.Out,"@%s",UsrDat->Nickname);
 	 HTM_DIV_End ();
 	}
@@ -1226,14 +1225,14 @@ void Pho_ShowUsrPhoto (const struct UsrData *UsrDat,const char *PhotoURL,
       /* Institution full name and institution country */
       if (UsrDat->InsCod > 0)
 	{
-	 fprintf (Gbl.F.Out,"<div class=\"ZOOM_TXT_LINE DAT_SMALL\">");
+	 HTM_DIV_Begin ("class=\"ZOOM_TXT_LINE DAT_SMALL\"");
 	 Ins_WriteInstitutionNameAndCty (UsrDat->InsCod);
 	 HTM_DIV_End ();
 	}
       /* User's country */
       else if (UsrDat->CtyCod > 0)
 	{
-	 fprintf (Gbl.F.Out,"<div class=\"ZOOM_TXT_LINE DAT_SMALL\">");
+	 HTM_DIV_Begin ("class=\"ZOOM_TXT_LINE DAT_SMALL\"");
 	 Cty_WriteCountryName (UsrDat->CtyCod,
 			       NULL);	// Don't put link to country
 	 HTM_DIV_End ();
@@ -1243,10 +1242,9 @@ void Pho_ShowUsrPhoto (const struct UsrData *UsrDat,const char *PhotoURL,
       Usr_GetMainDeg (UsrDat->UsrCod,MainDegreeShrtName,&MaxRole);
       if (MainDegreeShrtName[0])
 	{
-	 fprintf (Gbl.F.Out,"<div class=\"ZOOM_TXT_LINE DAT_SMALL\">");
-	 fprintf (Gbl.F.Out,"<div class=\"ZOOM_DEG\""
-		            " style=\"background-image:url('%s/%s');\">",
-		  Cfg_URL_ICON_PUBLIC,Rol_Icons[MaxRole]);
+	 HTM_DIV_Begin ("class=\"ZOOM_TXT_LINE DAT_SMALL\"");
+	 HTM_DIV_Begin ("class=\"ZOOM_DEG\" style=\"background-image:url('%s/%s');\"",
+		        Cfg_URL_ICON_PUBLIC,Rol_Icons[MaxRole]);
 	 fprintf (Gbl.F.Out,"%s",
 		  MainDegreeShrtName);
 	 HTM_DIV_End ();
@@ -1257,7 +1255,7 @@ void Pho_ShowUsrPhoto (const struct UsrData *UsrDat,const char *PhotoURL,
       if (UsrDat->Nickname[0])	// Get social data only if nickname is retrieved (in some actions)
         {
 	 Fol_GetNumFollow (UsrDat->UsrCod,&NumFollowing,&NumFollowers);
-	 fprintf (Gbl.F.Out,"<div class=\"ZOOM_TXT_LINE\">");
+	 HTM_DIV_Begin ("class=\"ZOOM_TXT_LINE\"");
 	 fprintf (Gbl.F.Out,"<span class=\"DAT_N_BOLD\">%u</span>"
 			    "<span class=\"DAT_SMALL\">&nbsp;%s&nbsp;</span>"
 			    "<span class=\"DAT_N_BOLD\">%u</span>"
@@ -2013,7 +2011,7 @@ static void Pho_PutLinkToCalculateDegreeStats (void)
       Deg_GetDataOfDegreeByCod (&Deg);
 
       /***** Start div *****/
-      fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+      HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 
       /***** Begin form *****/
       Frm_StartForm (ActCalPhoDeg);
@@ -2490,8 +2488,8 @@ static void Pho_ShowDegreeAvgPhotoAndStat (struct Degree *Deg,
 		      NumStds > 0 ? (int) (((NumStdsWithPhoto * 100.0) / NumStds) + 0.5) :
 				    0);
 	    Frm_SetUniqueId (IdCaption);
-	    fprintf (Gbl.F.Out,"<div id=\"%s\" class=\"NOT_SHOWN\">",IdCaption);
-	    fprintf (Gbl.F.Out,"<div class=\"ZOOM_TXT_LINE DAT_N\">");
+	    HTM_DIV_Begin ("id=\"%s\" class=\"NOT_SHOWN\"",IdCaption);
+	    HTM_DIV_Begin ("class=\"ZOOM_TXT_LINE DAT_N\"");
 	    fprintf (Gbl.F.Out,"%s",PhotoCaption);
 	    HTM_DIV_End ();
 	    HTM_DIV_End ();
@@ -2517,7 +2515,7 @@ static void Pho_ShowDegreeAvgPhotoAndStat (struct Degree *Deg,
             PhotoWidth,PhotoHeight);
 
    /***** Caption *****/
-   fprintf (Gbl.F.Out,"<div class=\"CLASSPHOTO_CAPTION\">");
+   HTM_DIV_Begin ("class=\"CLASSPHOTO_CAPTION\"");
    fprintf (Gbl.F.Out,"%s<br />"
 	              "%d&nbsp;%s<br />"
 	              "%d&nbsp;%s<br />"
diff --git a/swad_profile.c b/swad_profile.c
index b442bff9..30287193 100644
--- a/swad_profile.c
+++ b/swad_profile.c
@@ -188,7 +188,7 @@ void Prf_RequestUserProfile (void)
    if (Gbl.Usrs.Me.Logged)
      {
       /***** Put link to show my public profile and users to follow *****/
-      fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+      HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
       Prf_PutLinkMyPublicProfile ();
       Fol_PutLinkWhoToFollow ();
       HTM_DIV_End ();
@@ -288,7 +288,7 @@ bool Prf_ShowUserProfile (struct UsrData *UsrDat)
       /***** Contextual links *****/
       if (Gbl.Usrs.Me.Logged)
 	{
-	 fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+	 HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 
 	 if (ItsMe)
 	    /* Put link to show another user's profile */
@@ -404,7 +404,7 @@ void Prf_ShowDetailsUserProfile (const struct UsrData *UsrDat)
 
    /***** Left list *****/
    /* Start left list */
-   fprintf (Gbl.F.Out,"<div class=\"PRF_FIG_LEFT_CONTAINER\">");
+   HTM_DIV_Begin ("class=\"PRF_FIG_LEFT_CONTAINER\"");
    fprintf (Gbl.F.Out,"<ul class=\"PRF_FIG_UL DAT_NOBR_N\">");
 
    /* Time since first click */
@@ -424,7 +424,7 @@ void Prf_ShowDetailsUserProfile (const struct UsrData *UsrDat)
    HTM_DIV_End ();
 
    /***** Right list *****/
-   fprintf (Gbl.F.Out,"<div class=\"PRF_FIG_RIGHT_CONTAINER\">");
+   HTM_DIV_Begin ("class=\"PRF_FIG_RIGHT_CONTAINER\"");
 
    UsrIsBannedFromRanking = Usr_CheckIfUsrBanned (UsrDat->UsrCod);
    if (!UsrIsBannedFromRanking)
@@ -1780,7 +1780,7 @@ static void Prf_ShowUsrInRanking (struct UsrData *UsrDat,unsigned Rank)
      {
       Frm_StartForm (ActSeeOthPubPrf);
       Usr_PutParamUsrCodEncrypted (UsrDat->EncryptedUsrCod);
-      fprintf (Gbl.F.Out,"<div class=\"RANK_USR\">");	// Limited width
+      HTM_DIV_Begin ("class=\"RANK_USR\"");	// Limited width
       Frm_LinkFormSubmit (Txt_Another_user_s_profile,"DAT_SMALL",NULL);
       Usr_WriteFirstNameBRSurnames (UsrDat);
       fprintf (Gbl.F.Out,"</a>");
diff --git a/swad_project.c b/swad_project.c
index 46011c14..2fdf419f 100644
--- a/swad_project.c
+++ b/swad_project.c
@@ -418,9 +418,9 @@ static void Prj_ShowFormToFilterByMy_All (void)
 	My_All <= (Prj_WhoseProjects_t) (Prj_NUM_WHOSE_PROJECTS - 1);
 	My_All++)
      {
-      fprintf (Gbl.F.Out,"<div class=\"%s\">",
-	       (Gbl.Prjs.Filter.My_All == My_All) ? "PREF_ON" :
-					            "PREF_OFF");
+      HTM_DIV_Begin ("class=\"%s\"",
+		     (Gbl.Prjs.Filter.My_All == My_All) ? "PREF_ON" :
+							  "PREF_OFF");
       Frm_StartForm (ActSeePrj);
       Filter.My_All = My_All;
       Filter.PreNon = Gbl.Prjs.Filter.PreNon;
@@ -454,9 +454,9 @@ static void Prj_ShowFormToFilterByPreassignedNonPreassig (void)
 	PreNon <= (Prj_PreassignedNonpreassig_t) (Prj_NUM_PREASSIGNED_NONPREASSIG - 1);
 	PreNon++)
      {
-      fprintf (Gbl.F.Out,"<div class=\"%s\">",
-	       (Gbl.Prjs.Filter.PreNon & (1 << PreNon)) ? "PREF_ON" :
-						          "PREF_OFF");
+      HTM_DIV_Begin ("class=\"%s\"",
+		     (Gbl.Prjs.Filter.PreNon & (1 << PreNon)) ? "PREF_ON" :
+								"PREF_OFF");
       Frm_StartForm (ActSeePrj);
       Filter.My_All = Gbl.Prjs.Filter.My_All;
       Filter.PreNon = Gbl.Prjs.Filter.PreNon ^ (1 << PreNon);	// Toggle
@@ -495,9 +495,9 @@ static void Prj_ShowFormToFilterByHidden (void)
 	HidVis <= (Prj_HiddenVisibl_t) (Prj_NUM_HIDDEN_VISIBL - 1);
 	HidVis++)
      {
-      fprintf (Gbl.F.Out,"<div class=\"%s\">",
-	       (Gbl.Prjs.Filter.HidVis & (1 << HidVis)) ? "PREF_ON" :
-						          "PREF_OFF");
+      HTM_DIV_Begin ("class=\"%s\"",
+		     (Gbl.Prjs.Filter.HidVis & (1 << HidVis)) ? "PREF_ON" :
+								"PREF_OFF");
       Frm_StartForm (ActSeePrj);
       Filter.My_All = Gbl.Prjs.Filter.My_All;
       Filter.PreNon = Gbl.Prjs.Filter.PreNon;
@@ -536,9 +536,9 @@ static void Prj_ShowFormToFilterByWarning (void)
 	Faultiness <= (Prj_Faultiness_t) (Prj_NUM_FAULTINESS - 1);
 	Faultiness++)
      {
-      fprintf (Gbl.F.Out,"<div class=\"%s\">",
-	       (Gbl.Prjs.Filter.Faulti & (1 << Faultiness)) ? "PREF_ON" :
-						              "PREF_OFF");
+      HTM_DIV_Begin ("class=\"%s\"",
+		     (Gbl.Prjs.Filter.Faulti & (1 << Faultiness)) ? "PREF_ON" :
+								    "PREF_OFF");
       Frm_StartForm (ActSeePrj);
       Filter.My_All = Gbl.Prjs.Filter.My_All;
       Filter.PreNon = Gbl.Prjs.Filter.PreNon;
@@ -2514,7 +2514,7 @@ static void Prj_PutFormsToRemEditOnePrj (const struct Project *Prj,
    if (Prj_CheckIfICanLockProjects ())
      {
       /* Put form to lock/unlock project edition */
-      fprintf (Gbl.F.Out,"<div id=\"prj_lck_%ld\">",Prj->PrjCod);
+      HTM_DIV_Begin ("id=\"prj_lck_%ld\"",Prj->PrjCod);
       Prj_FormLockUnlock (Prj);
       HTM_DIV_End ();
      }
diff --git a/swad_record.c b/swad_record.c
index 240be20c..48473ed3 100644
--- a/swad_record.c
+++ b/swad_record.c
@@ -976,13 +976,14 @@ static void Rec_ListRecordsGsts (Rec_SharedRecordViewType_t TypeOfView)
 
    if (TypeOfView == Rec_SHA_RECORD_LIST)	// Listing several records
      {
-      fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+      HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 
       /* Link to print view */
       Frm_StartForm (ActPrnRecSevGst);
       Usr_PutHiddenParSelectedUsrsCods ();
       Rec_ShowLinkToPrintPreviewOfRecords ();
       Frm_EndForm ();
+
       HTM_DIV_End ();
      }
 
@@ -1006,19 +1007,20 @@ static void Rec_ListRecordsGsts (Rec_SharedRecordViewType_t TypeOfView)
 	           "record_%u",
 		   NumUsr);
 	 Lay_StartSection (RecordSectionId);
-	 fprintf (Gbl.F.Out,"<div class=\"REC_USR\"");
+
 	 if (Gbl.Action.Act == ActPrnRecSevGst &&
 	     NumUsr != 0 &&
 	     (NumUsr % Gbl.Usrs.Listing.RecsPerPag) == 0)
-	    fprintf (Gbl.F.Out," style=\"page-break-before:always;\"");
-	 fprintf (Gbl.F.Out,">");
+	    HTM_DIV_Begin ("class=\"REC_USR\" style=\"page-break-before:always;\"");
+	 else
+	    HTM_DIV_Begin ("class=\"REC_USR\"");
 
 	 /* Show optional alert */
 	 if (UsrDat.UsrCod == Gbl.Usrs.Other.UsrDat.UsrCod)	// Selected user
 	    Ale_ShowAlerts (NULL);
 
 	 /* Shared record */
-	 fprintf (Gbl.F.Out,"<div class=\"REC_LEFT\">");
+	 HTM_DIV_Begin ("class=\"REC_LEFT\"");
 	 Rec_ShowSharedUsrRecord (TypeOfView,&UsrDat,RecordSectionId);
 	 HTM_DIV_End ();
 
@@ -1069,7 +1071,7 @@ static void Rec_ShowRecordOneStdCrs (void)
    Rec_GetListRecordFieldsInCurrentCrs ();
 
    /***** Put contextual links *****/
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 
    /* Link to edit record fields */
    if (Gbl.Usrs.Me.Role.Logged == Rol_TCH)
@@ -1089,10 +1091,10 @@ static void Rec_ShowRecordOneStdCrs (void)
    Ale_ShowAlerts (NULL);
 
    /***** Start container for this user *****/
-   fprintf (Gbl.F.Out,"<div class=\"REC_USR\">");
+   HTM_DIV_Begin ("class=\"REC_USR\"");
 
    /***** Shared record *****/
-   fprintf (Gbl.F.Out,"<div class=\"REC_LEFT\">");
+   HTM_DIV_Begin ("class=\"REC_LEFT\"");
    Rec_ShowSharedUsrRecord (Rec_SHA_RECORD_LIST,&Gbl.Usrs.Other.UsrDat,NULL);
    HTM_DIV_End ();
 
@@ -1105,7 +1107,7 @@ static void Rec_ShowRecordOneStdCrs (void)
             ItsMe = Usr_ItsMe (Gbl.Usrs.Other.UsrDat.UsrCod);
             if (ItsMe)
 	      {
-	       fprintf (Gbl.F.Out,"<div class=\"REC_RIGHT\">");
+	       HTM_DIV_Begin ("class=\"REC_RIGHT\"");
 	       Rec_ShowCrsRecord (Rec_CRS_MY_RECORD_AS_STUDENT_FORM,&Gbl.Usrs.Other.UsrDat,NULL);
 	       HTM_DIV_End ();
 	      }
@@ -1113,7 +1115,7 @@ static void Rec_ShowRecordOneStdCrs (void)
          case Rol_NET:
          case Rol_TCH:
          case Rol_SYS_ADM:
-	    fprintf (Gbl.F.Out,"<div class=\"REC_RIGHT\">");
+	    HTM_DIV_Begin ("class=\"REC_RIGHT\"");
 	    Rec_ShowCrsRecord (Rec_CRS_LIST_ONE_RECORD,&Gbl.Usrs.Other.UsrDat,NULL);
 	    HTM_DIV_End ();
 	    break;
@@ -1172,7 +1174,7 @@ static void Rec_ListRecordsStds (Rec_SharedRecordViewType_t ShaTypeOfView,
 
    if (ShaTypeOfView == Rec_SHA_RECORD_LIST)
      {
-      fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+      HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 
       /* Link to edit record fields */
       if (Gbl.Usrs.Me.Role.Logged == Rol_TCH)
@@ -1183,6 +1185,7 @@ static void Rec_ListRecordsStds (Rec_SharedRecordViewType_t ShaTypeOfView,
       Usr_PutHiddenParSelectedUsrsCods ();
       Rec_ShowLinkToPrintPreviewOfRecords ();
       Frm_EndForm ();
+
       HTM_DIV_End ();
      }
 
@@ -1208,19 +1211,20 @@ static void Rec_ListRecordsStds (Rec_SharedRecordViewType_t ShaTypeOfView,
 		      "record_%u",
 		      NumUsr);
 	    Lay_StartSection (RecordSectionId);
-	    fprintf (Gbl.F.Out,"<div class=\"REC_USR\"");
-            if (Gbl.Action.Act == ActPrnRecSevStd &&
-                NumUsr != 0 &&
-                (NumUsr % Gbl.Usrs.Listing.RecsPerPag) == 0)
-               fprintf (Gbl.F.Out," style=\"page-break-before:always;\"");
-            fprintf (Gbl.F.Out,">");
+
+	    if (Gbl.Action.Act == ActPrnRecSevStd &&
+		NumUsr != 0 &&
+		(NumUsr % Gbl.Usrs.Listing.RecsPerPag) == 0)
+	       HTM_DIV_Begin ("class=\"REC_USR\" style=\"page-break-before:always;\"");
+	    else
+	       HTM_DIV_Begin ("class=\"REC_USR\"");
 
 	    /* Show optional alert */
 	    if (UsrDat.UsrCod == Gbl.Usrs.Other.UsrDat.UsrCod)	// Selected user
                Ale_ShowAlerts (NULL);
 
             /* Shared record */
-            fprintf (Gbl.F.Out,"<div class=\"REC_LEFT\">");
+            HTM_DIV_Begin ("class=\"REC_LEFT\"");
             Rec_ShowSharedUsrRecord (ShaTypeOfView,&UsrDat,RecordSectionId);
             HTM_DIV_End ();
 
@@ -1234,7 +1238,7 @@ static void Rec_ListRecordsStds (Rec_SharedRecordViewType_t ShaTypeOfView,
 		   (Gbl.Usrs.Me.Role.Logged == Rol_STD &&	// I am student in this course...
 		    ItsMe))					// ...and it's me
 		 {
-		  fprintf (Gbl.F.Out,"<div class=\"REC_RIGHT\">");
+		  HTM_DIV_Begin ("class=\"REC_RIGHT\"");
 		  Rec_ShowCrsRecord (CrsTypeOfView,&UsrDat,RecordSectionId);
                   HTM_DIV_End ();
 		 }
@@ -1299,7 +1303,7 @@ static void Rec_ShowRecordOneTchCrs (void)
    ShowOfficeHours = Rec_GetParamShowOfficeHours ();
 
    /***** Show contextual menu *****/
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 
    /* Show office hours? */
    Rec_WriteFormShowOfficeHoursOneTch (ShowOfficeHours);
@@ -1318,17 +1322,17 @@ static void Rec_ShowRecordOneTchCrs (void)
    HTM_DIV_End ();
 
    /***** Start container for this user *****/
-   fprintf (Gbl.F.Out,"<div class=\"REC_USR\">");
+   HTM_DIV_Begin ("class=\"REC_USR\"");
 
    /***** Shared record *****/
-   fprintf (Gbl.F.Out,"<div class=\"REC_LEFT\">");
+   HTM_DIV_Begin ("class=\"REC_LEFT\"");
    Rec_ShowSharedUsrRecord (Rec_SHA_RECORD_LIST,&Gbl.Usrs.Other.UsrDat,NULL);
    HTM_DIV_End ();
 
    /***** Office hours *****/
    if (ShowOfficeHours)
      {
-      fprintf (Gbl.F.Out,"<div class=\"REC_RIGHT\">");
+      HTM_DIV_Begin ("class=\"REC_RIGHT\"");
       Gbl.TimeTable.Type = TT_TUTORING_TIMETABLE;
       Box_StartBox (Width,Txt_TIMETABLE_TYPES[Gbl.TimeTable.Type],NULL,
                     Hlp_USERS_Teachers_timetable,Box_NOT_CLOSABLE);
@@ -1389,7 +1393,7 @@ static void Rec_ListRecordsTchs (Rec_SharedRecordViewType_t TypeOfView)
    if (Gbl.Action.Act == ActSeeRecSevTch)
      {
       /***** Show contextual menu *****/
-      fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+      HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 
       /* Show office hours? */
       Rec_WriteFormShowOfficeHoursSeveralTchs (ShowOfficeHours);
@@ -1429,26 +1433,27 @@ static void Rec_ListRecordsTchs (Rec_SharedRecordViewType_t TypeOfView)
 		      "record_%u",
 		      NumUsr);
 	    Lay_StartSection (RecordSectionId);
-	    fprintf (Gbl.F.Out,"<div class=\"REC_USR\"");
-            if (Gbl.Action.Act == ActPrnRecSevTch &&
-                NumUsr != 0 &&
-                (NumUsr % Gbl.Usrs.Listing.RecsPerPag) == 0)
-               fprintf (Gbl.F.Out," style=\"page-break-before:always;\"");
-            fprintf (Gbl.F.Out,">");
+
+	    if (Gbl.Action.Act == ActPrnRecSevTch &&
+		NumUsr != 0 &&
+		(NumUsr % Gbl.Usrs.Listing.RecsPerPag) == 0)
+	       HTM_DIV_Begin ("class=\"REC_USR\" style=\"page-break-before:always;\"");
+	    else
+	       HTM_DIV_Begin ("class=\"REC_USR\"");
 
 	    /* Show optional alert */
 	    if (UsrDat.UsrCod == Gbl.Usrs.Other.UsrDat.UsrCod)	// Selected user
 	       Ale_ShowAlerts (NULL);
 
 	    /* Shared record */
-            fprintf (Gbl.F.Out,"<div class=\"REC_LEFT\">");
+            HTM_DIV_Begin ("class=\"REC_LEFT\"");
             Rec_ShowSharedUsrRecord (TypeOfView,&UsrDat,RecordSectionId);
             HTM_DIV_End ();
 
             /* Office hours */
             if (ShowOfficeHours)
               {
-	       fprintf (Gbl.F.Out,"<div class=\"REC_RIGHT\">");
+	       HTM_DIV_Begin ("class=\"REC_RIGHT\"");
                Gbl.TimeTable.Type = TT_TUTORING_TIMETABLE;
 	       Box_StartBox (Width,Txt_TIMETABLE_TYPES[Gbl.TimeTable.Type],NULL,
 	                     Hlp_USERS_Teachers_timetable,Box_NOT_CLOSABLE);
@@ -2104,7 +2109,7 @@ void Rec_ShowSharedRecordUnmodifiable (struct UsrData *UsrDat)
    UsrDat->Accepted = Usr_CheckIfUsrHasAcceptedInCurrentCrs (UsrDat);
 
    /***** Show user's record *****/
-   fprintf (Gbl.F.Out,"<div class=\"CM\">");
+   HTM_DIV_Begin ("class=\"CM\"");
    Rec_ShowSharedUsrRecord (Rec_SHA_OTHER_USR_CHECK,UsrDat,NULL);
    HTM_DIV_End ();
   }
@@ -2479,7 +2484,7 @@ static void Rec_PutIconsCommands (void)
 				                 Gbl.Record.UsrDat);
 
       /***** Start container *****/
-      fprintf (Gbl.F.Out,"<div class=\"FRAME_ICO\">");
+      HTM_DIV_Begin ("class=\"FRAME_ICO\"");
 
       if (ItsMe)
          /***** Button to edit my record card *****/
@@ -2746,7 +2751,7 @@ static void Rec_ShowPhoto (struct UsrData *UsrDat)
 static void Rec_ShowFullName (struct UsrData *UsrDat)
   {
    HTM_TD_Begin ("class=\"REC_C2_MID LT\"");
-   fprintf (Gbl.F.Out,"<div class=\"REC_NAME\">");
+   HTM_DIV_Begin ("class=\"REC_NAME\"");
 
    /***** First name *****/
    fprintf (Gbl.F.Out,"%s<br />",UsrDat->FirstName);
@@ -2772,7 +2777,7 @@ static void Rec_ShowNickname (struct UsrData *UsrDat,bool PutFormLinks)
    bool ItsMe;
 
    HTM_TD_Begin ("class=\"REC_C2_MID LB\"");
-   fprintf (Gbl.F.Out,"<div class=\"REC_NICK\">");
+   HTM_DIV_Begin ("class=\"REC_NICK\"");
    if (UsrDat->Nickname[0])
      {
       if (PutFormLinks)
@@ -2840,7 +2845,7 @@ static void Rec_ShowEmail (struct UsrData *UsrDat,const char *ClassForm)
    HTM_TD_Begin ("class=\"REC_C2_BOT REC_DAT_BOLD LM\"");
    if (UsrDat->Email[0])
      {
-      fprintf (Gbl.F.Out,"<div class=\"REC_EMAIL\">");	// Limited width
+      HTM_DIV_Begin ("class=\"REC_EMAIL\"");	// Limited width
       if (Mai_ICanSeeOtherUsrEmail (UsrDat))
 	 fprintf (Gbl.F.Out,"<a href=\"mailto:%s\" class=\"REC_DAT_BOLD\">"
 			    "%s"
@@ -3765,7 +3770,7 @@ static void Rec_WriteLinkToDataProtectionClause (void)
   {
    extern const char *Txt_DATA_PROTECTION_CLAUSE;
 
-   fprintf (Gbl.F.Out,"<div class=\"CM\">");
+   HTM_DIV_Begin ("class=\"CM\"");
    fprintf (Gbl.F.Out,"<a class=\"TIT\" href=\"%s/\" target=\"_blank\">%s</a>",
             Cfg_URL_DATA_PROTECTION_PUBLIC,
             Txt_DATA_PROTECTION_CLAUSE);
@@ -3963,10 +3968,10 @@ void Rec_ShowMySharedRecordAndMore (void)
      }
 
    /***** Start container *****/
-   fprintf (Gbl.F.Out,"<div class=\"REC_USR\">");
+   HTM_DIV_Begin ("class=\"REC_USR\"");
 
    /***** Left part *****/
-   fprintf (Gbl.F.Out,"<div class=\"REC_LEFT\">");
+   HTM_DIV_Begin ("class=\"REC_LEFT\"");
 
    /* My shared record card */
    Rec_ShowSharedUsrRecord (Rec_SHA_MY_RECORD_FORM,&Gbl.Usrs.Me.UsrDat,NULL);
@@ -3975,7 +3980,7 @@ void Rec_ShowMySharedRecordAndMore (void)
 
    /***** Right part *****/
    /* Start container for right part */
-   fprintf (Gbl.F.Out,"<div class=\"REC_RIGHT\">");
+   HTM_DIV_Begin ("class=\"REC_RIGHT\"");
 
    /* My institution, centre and department */
    Rec_ShowFormMyInsCtrDpt (IAmATeacher);
diff --git a/swad_report.c b/swad_report.c
index d3a9fec7..65665058 100644
--- a/swad_report.c
+++ b/swad_report.c
@@ -274,7 +274,7 @@ static void Rep_PutLinkToMyUsageReport (struct Rep_Report *Report)
    Rep_TitleReport (&Report->CurrentTimeUTC);
 
    /***** Put anchor and report filename *****/
-   fprintf (Gbl.F.Out,"<div class=\"FILENAME_TXT CM\">");
+   HTM_DIV_Begin ("class=\"FILENAME_TXT CM\"");
    fprintf (Gbl.F.Out,"<a href=\"%s\" class=\"FILENAME_TXT\""
 		      " title=\"%s\" target=\"_blank\">"
                       "<img src=\"%s/file-alt.svg\" alt=\"%s\""
@@ -287,7 +287,8 @@ static void Rep_PutLinkToMyUsageReport (struct Rep_Report *Report)
             Txt_Report,
 	    Report->FilenameReport);
    HTM_DIV_End ();
-   fprintf (Gbl.F.Out,"<div class=\"DAT_LIGHT\">");
+
+   HTM_DIV_Begin ("class=\"DAT_LIGHT\"");
    fprintf (Gbl.F.Out,"%s",
             Txt_This_link_will_remain_active_as_long_as_your_user_s_account_exists);
    HTM_DIV_End ();
@@ -306,7 +307,7 @@ static void Rep_TitleReport (struct Rep_CurrentTimeUTC *CurrentTimeUTC)
    extern const char *Txt_User[Usr_NUM_SEXS];
    extern const char *Txt_Date;
 
-   fprintf (Gbl.F.Out,"<div class=\"TITLE_REPORT DAT\">");
+   HTM_DIV_Begin ("class=\"TITLE_REPORT DAT\"");
 
    /***** User *****/
    fprintf (Gbl.F.Out,"%s: <span class=\"DAT_N_BOLD\">%s</span>",
diff --git a/swad_search.c b/swad_search.c
index e1467edf..3852a9d3 100644
--- a/swad_search.c
+++ b/swad_search.c
@@ -134,7 +134,7 @@ static void Sch_PutFormToSearchWithWhatToSearchAndScope (Act_Action_t Action,Hie
    Sch_WhatToSearch_t WhatToSearch;
 
    /***** Start box *****/
-   fprintf (Gbl.F.Out,"<div class=\"CM\">");
+   HTM_DIV_Begin ("class=\"CM\"");
    Box_StartBox (NULL,Txt_Search,Crs_PutIconToSelectMyCourses,
                  Hlp_START_Search,Box_NOT_CLOSABLE);
 
@@ -143,7 +143,7 @@ static void Sch_PutFormToSearchWithWhatToSearchAndScope (Act_Action_t Action,Hie
 
    /***** Scope (whole platform, current country, current institution,
                  current centre, current degree or current course) *****/
-   fprintf (Gbl.F.Out,"<div class=\"CM\">");
+   HTM_DIV_Begin ("class=\"CM\"");
    fprintf (Gbl.F.Out,"<label class=\"%s\">%s:&nbsp;",
             The_ClassFormInBox[Gbl.Prefs.Theme],Txt_Scope);
    Gbl.Scope.Allowed = 1 << Hie_SYS |
@@ -228,13 +228,15 @@ static bool Sch_CheckIfIHavePermissionToSearch (Sch_WhatToSearch_t WhatToSearch)
 
 void Sch_PutFormToSearchInPageTopHeading (void)
   {
+   HTM_DIV_Begin ("id=\"head_row_1_search\"");
+
    /***** Put form *****/
-   fprintf (Gbl.F.Out,"<div id=\"head_row_1_search\">");
    Frm_StartForm (ActSch);
    Sco_PutParamScope ("ScopeSch",Hie_SYS);
    Sch_PutInputStringToSearch ("head_search_text");
    Sch_PutMagnifyingGlassButton ("search-white.svg");
    Frm_EndForm ();
+
    HTM_DIV_End ();	// head_row_1_search
   }
 
diff --git a/swad_setting.c b/swad_setting.c
index 08a17de9..28490627 100644
--- a/swad_setting.c
+++ b/swad_setting.c
@@ -79,32 +79,41 @@ void Set_EditSettings (void)
    /***** Internationalization: language, first day of week, date format *****/
    Box_StartBox (NULL,Txt_Internationalization,NULL,
                  Hlp_PROFILE_Settings_internationalization,Box_NOT_CLOSABLE);
-   fprintf (Gbl.F.Out,"<div class=\"FRAME_INLINE\">");
+
+   HTM_DIV_Begin ("class=\"FRAME_INLINE\"");
    Lan_PutBoxToSelectLanguage ();		// 1. Language
    HTM_DIV_End ();
-   fprintf (Gbl.F.Out,"<div class=\"FRAME_INLINE\">");
+
+   HTM_DIV_Begin ("class=\"FRAME_INLINE\"");
    Cal_PutIconsToSelectFirstDayOfWeek ();	// 2. First day of week
    HTM_DIV_End ();
-   fprintf (Gbl.F.Out,"<div class=\"FRAME_INLINE\">");
+
+   HTM_DIV_Begin ("class=\"FRAME_INLINE\"");
    Dat_PutBoxToSelectDateFormat ();		// 3. Date format
    HTM_DIV_End ();
+
    Box_EndBox ();
 
    /***** Design: icon set, menu, theme, side columns *****/
    Box_StartBox (NULL,Txt_Design,NULL,
                  Hlp_PROFILE_Settings_design,Box_NOT_CLOSABLE);
-   fprintf (Gbl.F.Out,"<div class=\"FRAME_INLINE\">");
+
+   HTM_DIV_Begin ("class=\"FRAME_INLINE\"");
    Ico_PutIconsToSelectIconSet ();		// 4. Icon set
    HTM_DIV_End ();
-   fprintf (Gbl.F.Out,"<div class=\"FRAME_INLINE\">");
+
+   HTM_DIV_Begin ("class=\"FRAME_INLINE\"");
    Mnu_PutIconsToSelectMenu ();			// 5. Menu
    HTM_DIV_End ();
-   fprintf (Gbl.F.Out,"<div class=\"FRAME_INLINE\">");
+
+   HTM_DIV_Begin ("class=\"FRAME_INLINE\"");
    The_PutIconsToSelectTheme ();		// 6. Theme
    HTM_DIV_End ();
-   fprintf (Gbl.F.Out,"<div class=\"FRAME_INLINE\">");
+
+   HTM_DIV_Begin ("class=\"FRAME_INLINE\"");
    Set_PutIconsToSelectSideCols ();		// 7. Side columns
    HTM_DIV_End ();
+
    Box_EndBox ();
 
    if (Gbl.Usrs.Me.Logged)
@@ -246,9 +255,8 @@ static void Set_PutIconsToSelectSideCols (void)
 	SideCols <= Lay_SHOW_BOTH_COLUMNS;
 	SideCols++)
      {
-      fprintf (Gbl.F.Out,"<div class=\"%s\">",
-               SideCols == Gbl.Prefs.SideCols ? "PREF_ON" :
-        	                                "PREF_OFF");
+      HTM_DIV_Begin ("class=\"%s\"",SideCols == Gbl.Prefs.SideCols ? "PREF_ON" :
+        	                                                     "PREF_OFF");
       Frm_StartForm (ActChgCol);
       Par_PutHiddenParamUnsigned ("SideCols",SideCols);
       snprintf (Icon,sizeof (Icon),
@@ -386,7 +394,7 @@ unsigned Set_GetParamSideCols (void)
 */
 void Set_StartSettingsHead (void)
   {
-   fprintf (Gbl.F.Out,"<div class=\"PREF_CONTAINERS\">");
+   HTM_DIV_Begin ("class=\"PREF_CONTAINERS\"");
   }
 
 void Set_EndSettingsHead (void)
@@ -396,7 +404,7 @@ void Set_EndSettingsHead (void)
 
 void Set_StartOneSettingSelector (void)
   {
-   fprintf (Gbl.F.Out,"<div class=\"PREF_CONTAINER\">");
+   HTM_DIV_Begin ("class=\"PREF_CONTAINER\"");
   }
 
 void Set_EndOneSettingSelector (void)
diff --git a/swad_statistic.c b/swad_statistic.c
index 0a98833d..4fafb62a 100644
--- a/swad_statistic.c
+++ b/swad_statistic.c
@@ -316,7 +316,7 @@ void Sta_AskShowCrsHits (void)
    unsigned long i;
 
    /***** Contextual links *****/
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 
    /* Put form to go to test edition and configuration */
    Sta_PutLinkToGlobalHits ();
@@ -523,7 +523,7 @@ void Sta_AskShowGblHits (void)
    Sta_ClicksGroupedBy_t ClicksGroupedBy;
 
    /***** Contextual links *****/
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 
    /* Put form to go to test edition and configuration */
    Sta_PutLinkToCourseHits ();
@@ -3995,7 +3995,7 @@ void Sta_ShowLastClicks (void)
    extern const char *Txt_Last_clicks_in_real_time;
 
    /***** Contextual links *****/
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 
    /* Put form to go to test edition and configuration */
    Sta_PutLinkToGlobalHits ();
@@ -4010,10 +4010,9 @@ void Sta_ShowLastClicks (void)
                  Hlp_USERS_Connected_last_clicks,Box_NOT_CLOSABLE);
 
    /***** Get and show last clicks *****/
-   fprintf (Gbl.F.Out,"<div id=\"lastclicks\""	// Used for AJAX based refresh
-	              " class=\"CM\">");
+   HTM_DIV_Begin ("id=\"lastclicks\" class=\"CM\"");	// Used for AJAX based refresh
    Sta_GetAndShowLastClicks ();
-   HTM_DIV_End ();				// Used for AJAX based refresh
+   HTM_DIV_End ();					// Used for AJAX based refresh
 
    /***** End box *****/
    Box_EndBox ();
diff --git a/swad_survey.c b/swad_survey.c
index 475177ce..d86f66a1 100644
--- a/swad_survey.c
+++ b/swad_survey.c
@@ -537,7 +537,7 @@ static void Svy_ShowOneSurvey (long SvyCod,struct SurveyQuestion *SvyQst,
    Lay_EndArticle ();
 
    /* Number of questions and number of distinct users who have already answered this survey */
-   fprintf (Gbl.F.Out,"<div class=\"%s\">",
+   HTM_DIV_Begin ("class=\"%s\"",
             Svy.Status.Visible ? "ASG_GRP" :
         	                 "ASG_GRP_LIGHT");
    fprintf (Gbl.F.Out,"%s: %u; %s: %u",
@@ -546,6 +546,7 @@ static void Svy_ShowOneSurvey (long SvyCod,struct SurveyQuestion *SvyQst,
             Txt_No_of_users,
             Svy.NumUsrs);
    HTM_DIV_End ();
+
    HTM_TD_End ();
 
    /* Status of the survey */
@@ -560,7 +561,7 @@ static void Svy_ShowOneSurvey (long SvyCod,struct SurveyQuestion *SvyQst,
       /* Possible button to answer this survey */
       if (Svy.Status.ICanAnswer)
 	{
-	 fprintf (Gbl.F.Out,"<div class=\"BUTTONS_AFTER_ALERT\">");
+	 HTM_DIV_Begin ("class=\"BUTTONS_AFTER_ALERT\"");
 
 	 Frm_StartForm (ActSeeSvy);
 	 Svy_PutParamSvyCod (Svy.SvyCod);
@@ -575,7 +576,7 @@ static void Svy_ShowOneSurvey (long SvyCod,struct SurveyQuestion *SvyQst,
       /* Possible button to see the result of the survey */
       else if (Svy.Status.ICanViewResults)
 	{
-	 fprintf (Gbl.F.Out,"<div class=\"BUTTONS_AFTER_ALERT\">");
+	 HTM_DIV_Begin ("class=\"BUTTONS_AFTER_ALERT\"");
 
 	 Frm_StartForm (ActSeeSvy);
 	 Svy_PutParamSvyCod (Svy.SvyCod);
@@ -610,9 +611,8 @@ static void Svy_ShowOneSurvey (long SvyCod,struct SurveyQuestion *SvyQst,
       HTM_TD_Begin ("class=\"LT COLOR%u\"",Gbl.RowEvenOdd);
 
    /* Scope of the survey */
-   fprintf (Gbl.F.Out,"<div class=\"%s\">",
-            Svy.Status.Visible ? "ASG_GRP" :
-        	                 "ASG_GRP_LIGHT");
+   HTM_DIV_Begin ("class=\"%s\"",Svy.Status.Visible ? "ASG_GRP" :
+        	                                      "ASG_GRP_LIGHT");
    fprintf (Gbl.F.Out,"%s: ",Txt_Scope);
    switch (Svy.Scope)
      {
@@ -641,9 +641,8 @@ static void Svy_ShowOneSurvey (long SvyCod,struct SurveyQuestion *SvyQst,
    HTM_DIV_End ();
 
    /* Users' roles who can answer the survey */
-   fprintf (Gbl.F.Out,"<div class=\"%s\">",
-            Svy.Status.Visible ? "ASG_GRP" :
-        	                 "ASG_GRP_LIGHT");
+   HTM_DIV_Begin ("class=\"%s\"",Svy.Status.Visible ? "ASG_GRP" :
+        	                                      "ASG_GRP_LIGHT");
    fprintf (Gbl.F.Out,"%s:<br />",Txt_Users);
    Rol_WriteSelectorRoles (1 << Rol_STD |
                            1 << Rol_NET |
@@ -662,9 +661,8 @@ static void Svy_ShowOneSurvey (long SvyCod,struct SurveyQuestion *SvyQst,
    Str_ChangeFormat (Str_FROM_HTML,Str_TO_RIGOROUS_HTML,
                      Txt,Cns_MAX_BYTES_TEXT,false);	// Convert from HTML to rigorous HTML
    Str_InsertLinks (Txt,Cns_MAX_BYTES_TEXT,60);	// Insert links
-   fprintf (Gbl.F.Out,"<div class=\"PAR %s\">",
-            Svy.Status.Visible ? "DAT" :
-        	                 "DAT_LIGHT");
+   HTM_DIV_Begin ("class=\"PAR %s\"",Svy.Status.Visible ? "DAT" :
+        	                                          "DAT_LIGHT");
    fprintf (Gbl.F.Out,"%s",Txt);
    HTM_DIV_End ();
    HTM_TD_End ();
@@ -2445,9 +2443,8 @@ static void Svy_GetAndWriteNamesOfGrpsAssociatedToSvy (struct Survey *Svy)
 			     Svy->SvyCod);
 
    /***** Write heading *****/
-   fprintf (Gbl.F.Out,"<div class=\"%s\">",
-            Svy->Status.Visible ? "ASG_GRP" :
-        	                  "ASG_GRP_LIGHT");
+   HTM_DIV_Begin ("class=\"%s\"",Svy->Status.Visible ? "ASG_GRP" :
+        	                                       "ASG_GRP_LIGHT");
    fprintf (Gbl.F.Out,"%s: ",NumRows == 1 ? Txt_Group  :
                                             Txt_Groups);
 
diff --git a/swad_syllabus.c b/swad_syllabus.c
index 41d21adb..5383c4a4 100644
--- a/swad_syllabus.c
+++ b/swad_syllabus.c
@@ -141,7 +141,7 @@ void Syl_PutFormWhichSyllabus (void)
 
    /***** Form to select which syllabus I want to see (lectures/practicals) *****/
    Frm_StartForm (ActSeeSyl);
-   fprintf (Gbl.F.Out,"<div class=\"CM\">");
+   HTM_DIV_Begin ("class=\"CM\"");
    fprintf (Gbl.F.Out,"<ul class=\"LIST_LEFT\">");
 
    for (WhichSyllabus = (Syl_WhichSyllabus_t) 0;
diff --git a/swad_tab.c b/swad_tab.c
index 4441578c..5ddf8ffe 100644
--- a/swad_tab.c
+++ b/swad_tab.c
@@ -99,7 +99,7 @@ void Tab_DrawTabs (void)
       };
 
    /***** Start tabs container *****/
-   fprintf (Gbl.F.Out,"<div class=\"%s\">",ClassHeadRow3[Gbl.Prefs.Theme]);
+   HTM_DIV_Begin ("class=\"%s\"",ClassHeadRow3[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"<nav id=\"tabs\">"
 	              "<ul class=\"LIST_TABS\">");
 
@@ -142,9 +142,9 @@ void Tab_DrawTabs (void)
 		  Tab_GetIcon (NumTab),
 		  Txt_TABS_TXT[NumTab],
 		  Txt_TABS_TXT[NumTab]);
-	 fprintf (Gbl.F.Out,"<div class=\"TAB_TXT %s\">",
-		  NumTab == Gbl.Action.Tab ? The_ClassTxtTabOn[Gbl.Prefs.Theme] :
-					     The_ClassTxtTabOff[Gbl.Prefs.Theme]);
+	 HTM_DIV_Begin ("class=\"TAB_TXT %s\"",
+			NumTab == Gbl.Action.Tab ? The_ClassTxtTabOn[Gbl.Prefs.Theme] :
+						   The_ClassTxtTabOff[Gbl.Prefs.Theme]);
 	 fprintf (Gbl.F.Out,"%s",Txt_TABS_TXT[NumTab]);
 	 HTM_DIV_End ();
 	 fprintf (Gbl.F.Out,"</a>");
diff --git a/swad_test.c b/swad_test.c
index ba393145..84fd063d 100644
--- a/swad_test.c
+++ b/swad_test.c
@@ -405,7 +405,7 @@ static void Tst_PutFormToViewTstResults (Act_Action_t Action)
   {
    extern const char *Txt_Results;
 
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
    Lay_PutContextualLinkIconText (Action,NULL,NULL,
 				  "tasks.svg",
 				  Txt_Results);
@@ -469,7 +469,7 @@ void Tst_ShowNewTest (void)
 	    HTM_TABLE_End ();
 
 	    /***** Test result will be saved? *****/
-	    fprintf (Gbl.F.Out,"<div class=\"CM\">");
+	    HTM_DIV_Begin ("class=\"CM\"");
 	    fprintf (Gbl.F.Out,"<label class=\"%s\">"
 			       "<input type=\"checkbox\" name=\"Save\""
 			       " value=\"Y\"",
@@ -558,7 +558,7 @@ void Tst_AssessTest (void)
 	 /***** Header *****/
 	 if (Gbl.Usrs.Me.IBelongToCurrentCrs)
 	   {
-	    fprintf (Gbl.F.Out,"<div class=\"TEST_SUBTITLE\">");
+	    HTM_DIV_Begin ("class=\"TEST_SUBTITLE\"");
 	    fprintf (Gbl.F.Out,Txt_Test_No_X_that_you_make_in_this_course,NumTst);
 	    HTM_DIV_End ();
 	   }
@@ -641,7 +641,7 @@ void Tst_ShowTstTotalMark (unsigned NumQsts,double TotalScore)
    double TotalScoreOverSCORE_MAX = TotalScore * Tst_SCORE_MAX / (double) NumQsts;
 
    /***** Write total mark ****/
-   fprintf (Gbl.F.Out,"<div class=\"DAT CM\">");
+   HTM_DIV_Begin ("class=\"DAT CM\"");
    fprintf (Gbl.F.Out,"%s: <span class=\"%s\">%.2lf (%.2lf %s %u)</span>",
 	    Txt_Score,
 	    (TotalScoreOverSCORE_MAX >= (double) TotalScoreOverSCORE_MAX / 2.0) ? "ANS_OK" :
@@ -1039,13 +1039,13 @@ static void Tst_WriteQstAndAnsTest (Tst_ActionToDoWithQuestions_t ActionToDoWith
    HTM_TD_Begin ("class=\"RT COLOR%u\"",Gbl.RowEvenOdd);
 
    /***** Write number of question *****/
-   fprintf (Gbl.F.Out,"<div class=\"BIG_INDEX\">");
+   HTM_DIV_Begin ("class=\"BIG_INDEX\"");
    fprintf (Gbl.F.Out,"%u",NumQst + 1);
    HTM_DIV_End ();
 
    /***** Write answer type (row[2]) *****/
    Gbl.Test.AnswerType = Tst_ConvertFromStrAnsTypDBToAnsTyp (row[2]);
-   fprintf (Gbl.F.Out,"<div class=\"DAT_SMALL\">");
+   HTM_DIV_Begin ("class=\"DAT_SMALL\"");
    fprintf (Gbl.F.Out,"%s",Txt_TST_STR_ANSWER_TYPES[Gbl.Test.AnswerType]);
    HTM_DIV_End ();
 
@@ -1105,7 +1105,7 @@ void Tst_WriteQstStem (const char *Stem,const char *ClassStem)
 	             StemRigorousHTML,StemLength,false);
 
    /***** Write the stem *****/
-   fprintf (Gbl.F.Out,"<div class=\"%s\">",ClassStem);
+   HTM_DIV_Begin ("class=\"%s\"",ClassStem);
    fprintf (Gbl.F.Out,"%s",StemRigorousHTML);
    HTM_DIV_End ();
 
@@ -1133,7 +1133,7 @@ static void Tst_PutFormToEditQstMedia (struct Media *Media,int NumMediaInForm,
       Med_SetParamNames (&ParamUploadMedia,NumMediaInForm);
 
       /***** Start container *****/
-      fprintf (Gbl.F.Out,"<div class=\"TEST_MED_EDIT_FORM\">");
+      HTM_DIV_Begin ("class=\"TEST_MED_EDIT_FORM\"");
 
       /***** Choice 1: No media *****/
       fprintf (Gbl.F.Out,"<label class=\"%s\">"
@@ -1209,7 +1209,7 @@ void Tst_WriteQstFeedback (const char *Feedback,const char *ClassFeedback)
 			   FeedbackRigorousHTML,FeedbackLength,false);
 
 	 /***** Write the feedback *****/
-	 fprintf (Gbl.F.Out,"<div class=\"%s\">",ClassFeedback);
+	 HTM_DIV_Begin ("class=\"%s\"",ClassFeedback);
 	 fprintf (Gbl.F.Out,"%s",FeedbackRigorousHTML);
 	 HTM_DIV_End ();
 
@@ -1285,7 +1285,7 @@ void Tst_ShowFormAskEditTsts (void)
    unsigned long NumRows;
 
    /***** Contextual menu *****/
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
    TsI_PutFormToImportQuestions ();	// Put link (form) to import questions from XML file
    HTM_DIV_End ();
 
@@ -2404,7 +2404,7 @@ void Tst_ListQuestionsToEdit (void)
       if ((NumRows = Tst_GetQuestions (&mysql_res)) != 0)	// Query database
         {
 	 /* Buttons for edition */
-         fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+         HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 	 if (Gbl.Test.XML.CreateXML)
 	    /* Create XML file for exporting questions
 	       and put a link to download it */
@@ -2917,13 +2917,13 @@ static void Tst_ListOneOrMoreQuestionsForEdition (unsigned long NumRows,
       HTM_TD_Begin ("class=\"RT COLOR%u\"",Gbl.RowEvenOdd);
 
       /* Write number of question */
-      fprintf (Gbl.F.Out,"<div class=\"BIG_INDEX\">");
+      HTM_DIV_Begin ("class=\"BIG_INDEX\"");
       fprintf (Gbl.F.Out,"%lu",NumRow + 1);
       HTM_DIV_End ();
 
       /* Write answer type (row[2]) */
       Gbl.Test.AnswerType = Tst_ConvertFromStrAnsTypDBToAnsTyp (row[2]);
-      fprintf (Gbl.F.Out,"<div class=\"DAT_SMALL\">");
+      HTM_DIV_Begin ("class=\"DAT_SMALL\"");
       fprintf (Gbl.F.Out,"%s",Txt_TST_STR_ANSWER_TYPES[Gbl.Test.AnswerType]);
       HTM_DIV_End ();
 
@@ -3412,7 +3412,7 @@ void Tst_WriteAnswersEdit (long QstCod)
             HTM_TD_Begin ("class=\"LT\"");
 
             /* Write the text of the answer and the media */
-            fprintf (Gbl.F.Out,"<div class=\"TEST_EDI\">");
+            HTM_DIV_Begin ("class=\"TEST_EDI\"");
             fprintf (Gbl.F.Out,"%s",Answer);
 	    Med_ShowMedia (&Gbl.Test.Answer.Options[NumOpt].Media,
 	                   "TEST_MED_EDIT_LIST_CONTAINER",
@@ -3420,10 +3420,11 @@ void Tst_WriteAnswersEdit (long QstCod)
             HTM_DIV_End ();
 
             /* Write the text of the feedback */
-            fprintf (Gbl.F.Out,"<div class=\"TEST_EDI_LIGHT\">");
+            HTM_DIV_Begin ("class=\"TEST_EDI_LIGHT\"");
             if (LengthFeedback)
 	       fprintf (Gbl.F.Out,"%s",Feedback);
             HTM_DIV_End ();
+
             HTM_TD_End ();
 
             HTM_TR_End ();
@@ -3881,20 +3882,23 @@ static void Tst_WriteChoiceAnsAssessTest (struct UsrData *UsrDat,
 
       /* Answer text and feedback */
       HTM_TD_Begin ("class=\"LT\"");
-      fprintf (Gbl.F.Out,"<div class=\"ANS_TXT\">");
+
+      HTM_DIV_Begin ("class=\"ANS_TXT\"");
       fprintf (Gbl.F.Out,"%s",Gbl.Test.Answer.Options[Indexes[NumOpt]].Text);
       Med_ShowMedia (&Gbl.Test.Answer.Options[Indexes[NumOpt]].Media,
                      "TEST_MED_SHOW_CONTAINER",
                      "TEST_MED_SHOW");
       HTM_DIV_End ();
+
       if (Gbl.Test.Config.Feedback == Tst_FEEDBACK_FULL_FEEDBACK)
 	 if (Gbl.Test.Answer.Options[Indexes[NumOpt]].Feedback)
 	    if (Gbl.Test.Answer.Options[Indexes[NumOpt]].Feedback[0])
 	      {
-	       fprintf (Gbl.F.Out,"<div class=\"TEST_EXA_LIGHT\">");
+	       HTM_DIV_Begin ("class=\"TEST_EXA_LIGHT\"");
 	       fprintf (Gbl.F.Out,"%s",Gbl.Test.Answer.Options[Indexes[NumOpt]].Feedback);
 	       HTM_DIV_End ();
 	      }
+
       HTM_TD_End ();
 
       HTM_TR_End ();
@@ -4192,8 +4196,7 @@ void Tst_WriteChoiceAnsViewMatch (long MchCod,unsigned QstInd,long QstCod,
 
       /***** Write letter for this option *****/
       HTM_TD_Begin ("class=\"MCH_TCH_BUTTON_TD\"");
-      fprintf (Gbl.F.Out,"<div class=\"MCH_TCH_BUTTON BT_%c\">",
-	       'A' + (char) NumOpt);
+      HTM_DIV_Begin ("class=\"MCH_TCH_BUTTON BT_%c\"",'A' + (char) NumOpt);
       fprintf (Gbl.F.Out,"%c",'a' + (char) NumOpt);
       HTM_DIV_End ();
       HTM_TD_End ();
@@ -4373,17 +4376,20 @@ static void Tst_WriteTextAnsAssessTest (struct UsrData *UsrDat,
 
          /* Answer text and feedback */
          HTM_TD_Begin ("class=\"LT\"");
-         fprintf (Gbl.F.Out,"<div class=\"ANS_0\">");
+
+         HTM_DIV_Begin ("class=\"ANS_0\"");
          fprintf (Gbl.F.Out,"%s",Gbl.Test.Answer.Options[NumOpt].Text);
          HTM_DIV_End ();
+
 	 if (Gbl.Test.Config.Feedback == Tst_FEEDBACK_FULL_FEEDBACK)
 	    if (Gbl.Test.Answer.Options[NumOpt].Feedback)
 	       if (Gbl.Test.Answer.Options[NumOpt].Feedback[0])
 		 {
-		  fprintf (Gbl.F.Out,"<div class=\"TEST_EXA_LIGHT\">");
+		  HTM_DIV_Begin ("class=\"TEST_EXA_LIGHT\"");
 		  fprintf (Gbl.F.Out,"%s",Gbl.Test.Answer.Options[NumOpt].Feedback);
 		  HTM_DIV_End ();
 		 }
+
 	 HTM_TD_End ();
 
 	 HTM_TR_End ();
@@ -5363,7 +5369,7 @@ static void Tst_PutFormEditOneQst (char Stem[Cns_MAX_BYTES_TEXT + 1],
 
       /***** Right column: content of the answer *****/
       HTM_TD_Begin ("class=\"TEST_EDI_ANS_RIGHT_COL COLOR%u\"",Gbl.RowEvenOdd);
-      fprintf (Gbl.F.Out,"<div id=\"ans_%u\"",NumOpt);
+      HTM_DIV_Begin ("id=\"ans_%u\"",NumOpt);
       if (!DisplayRightColumn)	// Answer does not have content
 	 fprintf (Gbl.F.Out," style=\"display:none;\"");	// Hide column
       fprintf (Gbl.F.Out,">");
diff --git a/swad_test_import.c b/swad_test_import.c
index fb58bdbe..1cab7b94 100644
--- a/swad_test_import.c
+++ b/swad_test_import.c
@@ -509,7 +509,7 @@ static void TsI_ImportQuestionsFromXMLBuffer (const char *XMLBuffer)
                  Hlp_ASSESSMENT_Tests,Box_NOT_CLOSABLE);
 
    /***** Print XML tree *****/
-   fprintf (Gbl.F.Out,"<div class=\"TEST_FILE_CONTENT\">");
+   HTM_DIV_Begin ("class=\"TEST_FILE_CONTENT\"");
    fprintf (Gbl.F.Out,"<textarea title=\"%s\" cols=\"60\" rows=\"5\""
 	              " spellcheck=\"false\" readonly>",
 	    Txt_XML_file_content);
@@ -1152,15 +1152,18 @@ static void TsI_WriteRowImportedQst (struct XMLElement *StemElem,
 
             /* Write the text and the feedback of the answer */
             HTM_TD_Begin ("class=\"LT\"");
-            fprintf (Gbl.F.Out,"<div class=\"%s\">",ClassStem);
+
+            HTM_DIV_Begin ("class=\"%s\"",ClassStem);
             fprintf (Gbl.F.Out,"%s",AnswerText);
             HTM_DIV_End ();
+
             if (AnswerFeedbackLength)
               {
-	       fprintf (Gbl.F.Out,"<div class=\"TEST_EDI_LIGHT\">");
+	       HTM_DIV_Begin ("class=\"TEST_EDI_LIGHT\"");
 	       fprintf (Gbl.F.Out,"%s",AnswerFeedback);
 	       HTM_DIV_End ();
               }
+
             HTM_TD_End ();
 
             HTM_TR_End ();
diff --git a/swad_theme.c b/swad_theme.c
index 2efe8ddb..5623034a 100644
--- a/swad_theme.c
+++ b/swad_theme.c
@@ -275,9 +275,8 @@ void The_PutIconsToSelectTheme (void)
 	Theme < The_NUM_THEMES;
 	Theme++)
      {
-      fprintf (Gbl.F.Out,"<div class=\"%s\">",
-               Theme == Gbl.Prefs.Theme ? "PREF_ON" :
-        	                          "PREF_OFF");
+      HTM_DIV_Begin ("class=\"%s\"",Theme == Gbl.Prefs.Theme ? "PREF_ON" :
+        	                                               "PREF_OFF");
       Frm_StartForm (ActChgThe);
       Par_PutHiddenParamString ("Theme",The_ThemeId[Theme]);
       snprintf (Icon,sizeof (Icon),
diff --git a/swad_timeline.c b/swad_timeline.c
index f5470c69..37f1c78a 100644
--- a/swad_timeline.c
+++ b/swad_timeline.c
@@ -1170,9 +1170,9 @@ static void TL_PutFormWhichUsrs (void)
 	WhichUsrs < TL_NUM_WHICH_USRS;
 	WhichUsrs++)
      {
-      fprintf (Gbl.F.Out,"<div class=\"%s\">",
-	       WhichUsrs == Gbl.Timeline.WhichUsrs ? "PREF_ON" :
-						     "PREF_OFF");
+      HTM_DIV_Begin ("class=\"%s\"",
+		     WhichUsrs == Gbl.Timeline.WhichUsrs ? "PREF_ON" :
+							   "PREF_OFF");
       Frm_StartForm (ActSeeSocTmlGbl);
       Par_PutHiddenParamUnsigned ("WhichUsrs",WhichUsrs);
       Ico_PutSettingIconLink (Icon[WhichUsrs],Txt_TIMELINE_WHICH_USERS[WhichUsrs]);
@@ -1288,7 +1288,7 @@ static void TL_ShowWarningYouDontFollowAnyUser (void)
       Ale_ShowAlert (Ale_WARNING,Txt_You_dont_follow_any_user);
 
       /***** Put link to show users to follow *****/
-      fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+      HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
       Fol_PutLinkWhoToFollow ();
       HTM_DIV_End ();
      }
@@ -1392,9 +1392,9 @@ static void TL_PutLinkToViewNewPublications (void)
 
    /***** Link to view (show hidden) new publications *****/
    // div is hidden. When new posts arrive to the client via AJAX, div is shown
-   fprintf (Gbl.F.Out,"<div id=\"view_new_posts_container\""
-	              " class=\"TL_WIDTH TL_SEP VERY_LIGHT_BLUE\""
-	              " style=\"display:none;\">");
+   HTM_DIV_Begin ("id=\"view_new_posts_container\""
+		  " class=\"TL_WIDTH TL_SEP VERY_LIGHT_BLUE\""
+		  " style=\"display:none;\"");
    fprintf (Gbl.F.Out,"<a href=\"\" class=\"%s\""
                       " onclick=\"moveNewTimelineToTimeline(); return false;\" />"
                       "%s (<span id=\"view_new_posts_count\">0</span>)"
@@ -1414,8 +1414,8 @@ static void TL_PutLinkToViewOldPublications (void)
    extern const char *Txt_See_more;
 
    /***** Animated link to view old publications *****/
-   fprintf (Gbl.F.Out,"<div id=\"view_old_posts_container\""
-	              " class=\"TL_WIDTH TL_SEP VERY_LIGHT_BLUE\">");
+   HTM_DIV_Begin ("id=\"view_old_posts_container\""
+	          " class=\"TL_WIDTH TL_SEP VERY_LIGHT_BLUE\"");
    fprintf (Gbl.F.Out,"<a href=\"\" class=\"%s\" onclick=\""
    		      "document.getElementById('get_old_timeline').style.display='none';"	// Icon to be hidden on click
 		      "document.getElementById('getting_old_timeline').style.display='';"	// Icon to be shown on click
@@ -1506,7 +1506,7 @@ static void TL_WriteNote (const struct TL_Note *SocNot,
       IAmTheAuthor = Usr_ItsMe (UsrDat.UsrCod);
 
       /***** Left: write author's photo *****/
-      fprintf (Gbl.F.Out,"<div class=\"TL_LEFT_PHOTO\">");
+      HTM_DIV_Begin ("class=\"TL_LEFT_PHOTO\"");
       ShowPhoto = Pho_ShowingUsrPhotoIsAllowed (&UsrDat,PhotoURL);
       Pho_ShowUsrPhoto (&UsrDat,ShowPhoto ? PhotoURL :
 					    NULL,
@@ -1514,7 +1514,7 @@ static void TL_WriteNote (const struct TL_Note *SocNot,
       HTM_DIV_End ();
 
       /***** Right: author's name, time, summary and buttons *****/
-      fprintf (Gbl.F.Out,"<div class=\"TL_RIGHT_CONT TL_RIGHT_WIDTH\">");
+      HTM_DIV_Begin ("class=\"TL_RIGHT_CONT TL_RIGHT_WIDTH\"");
 
       /* Write author's full name and nickname */
       TL_WriteAuthorNote (&UsrDat);
@@ -1578,21 +1578,21 @@ static void TL_WriteNote (const struct TL_Note *SocNot,
 	       case TL_NOTE_INS_DOC_PUB_FILE:
 	       case TL_NOTE_INS_SHA_PUB_FILE:
 		  /* Write location (institution) in hierarchy */
-		  fprintf (Gbl.F.Out,"<div class=\"TL_LOC\">");
+		  HTM_DIV_Begin ("class=\"TL_LOC\"");
 		  fprintf (Gbl.F.Out,"%s: %s",Txt_Institution,Ins.ShrtName);
 		  HTM_DIV_End ();
 		  break;
 	       case TL_NOTE_CTR_DOC_PUB_FILE:
 	       case TL_NOTE_CTR_SHA_PUB_FILE:
 		  /* Write location (centre) in hierarchy */
-		  fprintf (Gbl.F.Out,"<div class=\"TL_LOC\">");
+		  HTM_DIV_Begin ("class=\"TL_LOC\"");
 		  fprintf (Gbl.F.Out,"%s: %s",Txt_Centre,Ctr.ShrtName);
 		  HTM_DIV_End ();
 		  break;
 	       case TL_NOTE_DEG_DOC_PUB_FILE:
 	       case TL_NOTE_DEG_SHA_PUB_FILE:
 		  /* Write location (degree) in hierarchy */
-		  fprintf (Gbl.F.Out,"<div class=\"TL_LOC\">");
+		  HTM_DIV_Begin ("class=\"TL_LOC\"");
 		  fprintf (Gbl.F.Out,"%s: %s",Txt_Degree,Deg.ShrtName);
 		  HTM_DIV_End ();
 		  break;
@@ -1601,13 +1601,13 @@ static void TL_WriteNote (const struct TL_Note *SocNot,
 	       case TL_NOTE_EXAM_ANNOUNCEMENT:
 	       case TL_NOTE_NOTICE:
 		  /* Write location (course) in hierarchy */
-		  fprintf (Gbl.F.Out,"<div class=\"TL_LOC\">");
+		  HTM_DIV_Begin ("class=\"TL_LOC\"");
 		  fprintf (Gbl.F.Out,"%s: %s",Txt_Course,Crs.ShrtName);
 		  HTM_DIV_End ();
 		  break;
 	       case TL_NOTE_FORUM_POST:
 		  /* Write forum name */
-		  fprintf (Gbl.F.Out,"<div class=\"TL_LOC\">");
+		  HTM_DIV_Begin ("class=\"TL_LOC\"");
 		  fprintf (Gbl.F.Out,"%s: %s",Txt_Forum,ForumName);
 		  HTM_DIV_End ();
 		  break;
@@ -1617,7 +1617,7 @@ static void TL_WriteNote (const struct TL_Note *SocNot,
 
 	 /* Write note summary */
 	 TL_GetNoteSummary (SocNot,SummaryStr);
-	 fprintf (Gbl.F.Out,"<div class=\"TL_TXT\">");
+	 HTM_DIV_Begin ("class=\"TL_TXT\"");
 	 fprintf (Gbl.F.Out,"%s",SummaryStr);
 	 HTM_DIV_End ();
 	}
@@ -1632,7 +1632,7 @@ static void TL_WriteNote (const struct TL_Note *SocNot,
       NumComments = TL_GetNumCommentsInNote (SocNot->NotCod);
 
       /* Put icon to add a comment */
-      fprintf (Gbl.F.Out,"<div class=\"TL_BOTTOM_LEFT\">");
+      HTM_DIV_Begin ("class=\"TL_BOTTOM_LEFT\"");
       if (SocNot->Unavailable)		// Unavailable notes can not be commented
 	 TL_PutIconCommentDisabled ();
       else
@@ -1640,27 +1640,25 @@ static void TL_WriteNote (const struct TL_Note *SocNot,
       HTM_DIV_End ();
 
       /* Start container for buttons and comments */
-      fprintf (Gbl.F.Out,"<div class=\"TL_BOTTOM_RIGHT TL_RIGHT_WIDTH\">");
+      HTM_DIV_Begin ("class=\"TL_BOTTOM_RIGHT TL_RIGHT_WIDTH\"");
 
       /* Start foot container */
-      fprintf (Gbl.F.Out,"<div class=\"TL_FOOT TL_RIGHT_WIDTH\">");
+      HTM_DIV_Begin ("class=\"TL_FOOT TL_RIGHT_WIDTH\"");
 
       /* Foot column 1: Fav zone */
-      fprintf (Gbl.F.Out,"<div id=\"fav_not_%s_%u\""
-	                 " class=\"TL_FAV_NOT TL_FAV_NOT_WIDTH\">",
-	       Gbl.UniqueNameEncrypted,NumDiv);
+      HTM_DIV_Begin ("id=\"fav_not_%s_%u\" class=\"TL_FAV_NOT TL_FAV_NOT_WIDTH\"",
+	             Gbl.UniqueNameEncrypted,NumDiv);
       TL_PutFormToFavUnfNote (SocNot,TL_SHOW_A_FEW_USRS);
       HTM_DIV_End ();
 
       /* Foot column 2: Share zone */
-      fprintf (Gbl.F.Out,"<div id=\"sha_not_%s_%u\""
-	                 " class=\"TL_SHA_NOT TL_SHA_NOT_WIDTH\">",
-	       Gbl.UniqueNameEncrypted,NumDiv);
+      HTM_DIV_Begin ("id=\"sha_not_%s_%u\" class=\"TL_SHA_NOT TL_SHA_NOT_WIDTH\"",
+	             Gbl.UniqueNameEncrypted,NumDiv);
       TL_PutFormToShaUnsNote (SocNot,TL_SHOW_A_FEW_USRS);
       HTM_DIV_End ();
 
       /* Foot column 3: Icon to remove this note */
-      fprintf (Gbl.F.Out,"<div class=\"TL_REM\">");
+      HTM_DIV_Begin ("class=\"TL_REM\"");
       if (IAmTheAuthor)
 	 TL_PutFormToRemovePublication (SocNot->NotCod);
       HTM_DIV_End ();
@@ -1714,8 +1712,7 @@ static void TL_WriteTopMessage (TL_TopMessage_t TopMessage,long UsrCod)
       UsrDat.UsrCod = UsrCod;
       if (Usr_ChkUsrCodAndGetAllUsrDataFromUsrCod (&UsrDat,Usr_DONT_GET_PREFS))	// Really we only need EncryptedUsrCod and FullName
 	{
-	 fprintf (Gbl.F.Out,"<div class=\"TL_TOP_CONT"
-	                    " TL_TOP_PUBLISHER TL_WIDTH\">");
+	 HTM_DIV_Begin ("class=\"TL_TOP_CONT TL_TOP_PUBLISHER TL_WIDTH\"");
 
 	 /***** Show user's name inside form to go to user's public profile *****/
 	 Frm_StartFormUnique (ActSeeOthPubPrf);
@@ -1728,6 +1725,7 @@ static void TL_WriteTopMessage (TL_TopMessage_t TopMessage,long UsrCod)
 
 	 /***** Show action made *****/
          fprintf (Gbl.F.Out," %s:",Txt_TIMELINE_NOTE_TOP_MESSAGES[TopMessage]);
+
          HTM_DIV_End ();
 	}
 
@@ -1746,7 +1744,7 @@ static void TL_WriteAuthorNote (const struct UsrData *UsrDat)
    extern const char *Txt_Another_user_s_profile;
    bool ItsMe = Usr_ItsMe (UsrDat->UsrCod);
 
-   fprintf (Gbl.F.Out,"<div class=\"TL_RIGHT_AUTHOR TL_RIGHT_AUTHOR_WIDTH\">");
+   HTM_DIV_Begin ("class=\"TL_RIGHT_AUTHOR TL_RIGHT_AUTHOR_WIDTH\"");
 
    /***** Show user's name inside form to go to user's public profile *****/
    Frm_StartFormUnique (ActSeeOthPubPrf);
@@ -1783,8 +1781,7 @@ static void TL_WriteDateTime (time_t TimeUTC)
    Frm_SetUniqueId (IdDateTime);
 
    /***** Container where the date-time is written *****/
-   fprintf (Gbl.F.Out,"<div id=\"%s\" class=\"TL_RIGHT_TIME DAT_LIGHT\">",
-            IdDateTime);
+   HTM_DIV_Begin ("id=\"%s\" class=\"TL_RIGHT_TIME DAT_LIGHT\"",IdDateTime);
    HTM_DIV_End ();
 
    /***** Script to write date and time in browser local time *****/
@@ -1844,7 +1841,7 @@ static void TL_GetAndWritePost (long PstCod)
    /***** Write content *****/
    if (Content[0])
      {
-      fprintf (Gbl.F.Out,"<div class=\"TL_TXT\">");
+      HTM_DIV_Begin ("class=\"TL_TXT\"");
       Msg_WriteMsgContent (Content,Cns_MAX_BYTES_LONG_TEXT,true,false);
       HTM_DIV_End ();
      }
@@ -1948,7 +1945,7 @@ static void TL_PutFormGoToAction (const struct TL_Note *SocNot)
        Gbl.Form.Inside)		// Inside another form
      {
       /***** Do not put form *****/
-      fprintf (Gbl.F.Out,"<div class=\"TL_FORM_OFF\">");
+      HTM_DIV_Begin ("class=\"TL_FORM_OFF\"");
       fprintf (Gbl.F.Out,"%s",Txt_TIMELINE_NOTE[SocNot->NoteType]);
       if (SocNot->Unavailable)
          fprintf (Gbl.F.Out," (%s)",Txt_not_available);
@@ -1956,7 +1953,7 @@ static void TL_PutFormGoToAction (const struct TL_Note *SocNot)
      }
    else			// Not inside another form
      {
-      fprintf (Gbl.F.Out,"<div class=\"TL_FORM\">");
+      HTM_DIV_Begin ("class=\"TL_FORM\"");
 
       /***** Parameters depending on the type of note *****/
       switch (SocNot->NoteType)
@@ -2321,7 +2318,7 @@ static void TL_PutFormToWriteNewPost (void)
                       "<li class=\"TL_WIDTH\">");
 
    /***** Left: write author's photo (my photo) *****/
-   fprintf (Gbl.F.Out,"<div class=\"TL_LEFT_PHOTO\">");
+   HTM_DIV_Begin ("class=\"TL_LEFT_PHOTO\"");
    ShowPhoto = Pho_ShowingUsrPhotoIsAllowed (&Gbl.Usrs.Me.UsrDat,PhotoURL);
    Pho_ShowUsrPhoto (&Gbl.Usrs.Me.UsrDat,ShowPhoto ? PhotoURL :
 						     NULL,
@@ -2329,10 +2326,10 @@ static void TL_PutFormToWriteNewPost (void)
    HTM_DIV_End ();
 
    /***** Right: author's name, time, summary and buttons *****/
-   fprintf (Gbl.F.Out,"<div class=\"TL_RIGHT_CONT TL_RIGHT_WIDTH\">");
+   HTM_DIV_Begin ("class=\"TL_RIGHT_CONT TL_RIGHT_WIDTH\"");
 
    /* Write author's full name and nickname */
-   fprintf (Gbl.F.Out,"<div class=\"TL_RIGHT_AUTHOR TL_RIGHT_AUTHOR_WIDTH\">");
+   HTM_DIV_Begin ("class=\"TL_RIGHT_AUTHOR TL_RIGHT_AUTHOR_WIDTH\"");
    fprintf (Gbl.F.Out,"<span class=\"DAT_N_BOLD\">%s</span>"
 		      "<span class=\"DAT_LIGHT\"> @%s</span>",
 	    Gbl.Usrs.Me.UsrDat.FullName,Gbl.Usrs.Me.UsrDat.Nickname);
@@ -2340,7 +2337,7 @@ static void TL_PutFormToWriteNewPost (void)
 
    /***** Form to write the post *****/
    /* Start container */
-   fprintf (Gbl.F.Out,"<div class=\"TL_FORM_NEW_PST TL_RIGHT_WIDTH\">");
+   HTM_DIV_Begin ("class=\"TL_FORM_NEW_PST TL_RIGHT_WIDTH\"");
 
    /* Begin form to write the post */
    TL_FormStart (ActRcvSocPstGbl,ActRcvSocPstUsr);
@@ -2383,8 +2380,7 @@ static void TL_PutTextarea (const char *Placeholder,const char *ClassTextArea)
             IdDivImgButton);
 
    /***** Start concealable div *****/
-   fprintf (Gbl.F.Out,"<div id=\"%s\" style=\"display:none;\">",
-            IdDivImgButton);
+   HTM_DIV_Begin ("id=\"%s\" style=\"display:none;\"",IdDivImgButton);
 
    /***** Help on editor *****/
    Lay_HelpPlainEditor ();
@@ -2500,7 +2496,7 @@ static void TL_PutIconToToggleCommentNote (const char UniqueId[Frm_MAX_BYTES_ID
    extern const char *Txt_Comment;
 
    /***** Link to toggle on/off the form to comment a note *****/
-   fprintf (Gbl.F.Out,"<div id=\"%s_ico\" class=\"TL_ICO_COM_OFF\">",UniqueId);
+   HTM_DIV_Begin ("id=\"%s_ico\" class=\"TL_ICO_COM_OFF\"",UniqueId);
    fprintf (Gbl.F.Out,"<a href=\"\""
                       " onclick=\"toggleNewComment ('%s');return false;\">"
                       "<img src=\"%s/edit.svg\" alt=\"%s\" title=\"%s\""
@@ -2521,7 +2517,7 @@ static void TL_PutIconCommentDisabled (void)
    extern const char *Txt_Comment;
 
    /***** Disabled icon to comment a note *****/
-   fprintf (Gbl.F.Out,"<div class=\"TL_ICO_COM_OFF TL_ICO_DISABLED\">");
+   HTM_DIV_Begin ("class=\"TL_ICO_COM_OFF TL_ICO_DISABLED\"");
    fprintf (Gbl.F.Out,"<img src=\"%s/edit.svg\""
 		      " alt=\"%s\" title=\"%s\""
 		      " class=\"ICO16x16\" />",
@@ -2542,13 +2538,12 @@ static void TL_PutHiddenFormToWriteNewCommentToNote (long NotCod,
    char PhotoURL[PATH_MAX + 1];
 
    /***** Start container *****/
-   fprintf (Gbl.F.Out,"<div id=\"%s\""
-		      " class=\"TL_FORM_NEW_COM TL_RIGHT_WIDTH\""
-		      " style=\"display:none;\">",
-	    IdNewComment);
+   HTM_DIV_Begin ("id=\"%s\" class=\"TL_FORM_NEW_COM TL_RIGHT_WIDTH\""
+		  " style=\"display:none;\"",
+	          IdNewComment);
 
    /***** Left: write author's photo (my photo) *****/
-   fprintf (Gbl.F.Out,"<div class=\"TL_COM_PHOTO\">");
+   HTM_DIV_Begin ("class=\"TL_COM_PHOTO\"");
    ShowPhoto = Pho_ShowingUsrPhotoIsAllowed (&Gbl.Usrs.Me.UsrDat,PhotoURL);
    Pho_ShowUsrPhoto (&Gbl.Usrs.Me.UsrDat,ShowPhoto ? PhotoURL :
 					             NULL,
@@ -2557,7 +2552,7 @@ static void TL_PutHiddenFormToWriteNewCommentToNote (long NotCod,
 
    /***** Right: form to write the comment *****/
    /* Start right container */
-   fprintf (Gbl.F.Out,"<div class=\"TL_COM_CONT TL_COMM_WIDTH\">");
+   HTM_DIV_Begin ("class=\"TL_COM_CONT TL_COMM_WIDTH\"");
 
    /* Begin form to write the post */
    TL_FormStart (ActRcvSocComGbl,ActRcvSocComUsr);
@@ -2632,10 +2627,9 @@ static void TL_WriteCommentsInNote (const struct TL_Note *SocNot)
 	 Frm_SetUniqueId (IdComments);
 
 	 /***** Link to toggle on/off comments *****/
-	 fprintf (Gbl.F.Out,"<div id=\"con_%s\""
-			    " class=\"TL_EXPAND_COM TL_RIGHT_WIDTH\""
-			    " style=\"display:none;\">",	// Initially hidden
-		  IdComments);
+	 HTM_DIV_Begin ("id=\"con_%s\" class=\"TL_EXPAND_COM TL_RIGHT_WIDTH\""
+			" style=\"display:none;\">",	// Initially hidden
+		        IdComments);
 	 TL_PutIconToToggleComments (IdComments,"angle-down.svg",
 	                              Txt_See_only_the_latest_COMMENTS);
 	 HTM_DIV_End ();
@@ -2651,9 +2645,8 @@ static void TL_WriteCommentsInNote (const struct TL_Note *SocNot)
 	 fprintf (Gbl.F.Out,"</ul>");
 
 	 /***** Link to toggle on/off comments *****/
-	 fprintf (Gbl.F.Out,"<div id=\"exp_%s\""
-			    " class=\"TL_EXPAND_COM TL_RIGHT_WIDTH\">",
-		  IdComments);
+	 HTM_DIV_Begin ("id=\"exp_%s\" class=\"TL_EXPAND_COM TL_RIGHT_WIDTH\"",
+		        IdComments);
 	 snprintf (Gbl.Title,sizeof (Gbl.Title),
 		   Txt_See_the_previous_X_COMMENTS,
 		   NumCommentsInitiallyHidden);
@@ -2743,9 +2736,10 @@ static void TL_WriteComment (struct TL_Comment *SocCom,
       /***** Write sharer/commenter if distinct to author *****/
       TL_WriteTopMessage (TopMessage,UsrCod);
 
-      fprintf (Gbl.F.Out,"<div class=\"TL_LEFT_PHOTO\">");
+      HTM_DIV_Begin ("class=\"TL_LEFT_PHOTO\"");
       HTM_DIV_End ();
-      fprintf (Gbl.F.Out,"<div class=\"TL_RIGHT_CONT TL_RIGHT_WIDTH\">");
+
+      HTM_DIV_Begin ("class=\"TL_RIGHT_CONT TL_RIGHT_WIDTH\"");
       fprintf (Gbl.F.Out,"<ul class=\"LIST_LEFT\">");
      }
 
@@ -2768,7 +2762,7 @@ static void TL_WriteComment (struct TL_Comment *SocCom,
       IAmTheAuthor = Usr_ItsMe (UsrDat.UsrCod);
 
       /***** Left: write author's photo *****/
-      fprintf (Gbl.F.Out,"<div class=\"TL_COM_PHOTO\">");
+      HTM_DIV_Begin ("class=\"TL_COM_PHOTO\"");
       ShowPhoto = Pho_ShowingUsrPhotoIsAllowed (&UsrDat,PhotoURL);
       Pho_ShowUsrPhoto (&UsrDat,ShowPhoto ? PhotoURL :
 					    NULL,
@@ -2776,7 +2770,7 @@ static void TL_WriteComment (struct TL_Comment *SocCom,
       HTM_DIV_End ();
 
       /***** Right: author's name, time, content, image and buttons *****/
-      fprintf (Gbl.F.Out,"<div class=\"TL_COM_CONT TL_COMM_WIDTH\">");
+      HTM_DIV_Begin ("class=\"TL_COM_CONT TL_COMM_WIDTH\"");
 
       /* Write author's full name and nickname */
       TL_WriteAuthorComment (&UsrDat);
@@ -2787,7 +2781,7 @@ static void TL_WriteComment (struct TL_Comment *SocCom,
       /* Write content of the comment */
       if (SocCom->Content[0])
 	{
-	 fprintf (Gbl.F.Out,"<div class=\"TL_TXT\">");
+	 HTM_DIV_Begin ("class=\"TL_TXT\"");
 	 Msg_WriteMsgContent (SocCom->Content,Cns_MAX_BYTES_LONG_TEXT,true,false);
 	 HTM_DIV_End ();
 	}
@@ -2797,17 +2791,16 @@ static void TL_WriteComment (struct TL_Comment *SocCom,
 	                            "TL_COM_MED TL_COMM_WIDTH");
 
       /* Start foot container */
-      fprintf (Gbl.F.Out,"<div class=\"TL_FOOT TL_COMM_WIDTH\">");
+      HTM_DIV_Begin ("class=\"TL_FOOT TL_COMM_WIDTH\"");
 
       /* Fav zone */
-      fprintf (Gbl.F.Out,"<div id=\"fav_com_%s_%u\""
-	                 " class=\"TL_FAV_COM TL_FAV_WIDTH\">",
-	       Gbl.UniqueNameEncrypted,NumDiv);
+      HTM_DIV_Begin ("id=\"fav_com_%s_%u\" class=\"TL_FAV_COM TL_FAV_WIDTH\"",
+	             Gbl.UniqueNameEncrypted,NumDiv);
       TL_PutFormToFavUnfComment (SocCom,TL_SHOW_A_FEW_USRS);
       HTM_DIV_End ();
 
       /* Put icon to remove this comment */
-      fprintf (Gbl.F.Out,"<div class=\"TL_REM\">");
+      HTM_DIV_Begin ("class=\"TL_REM\"");
       if (IAmTheAuthor && !ShowCommentAlone)
 	 TL_PutFormToRemoveComment (SocCom->PubCod);
       HTM_DIV_End ();
@@ -2841,7 +2834,7 @@ static void TL_WriteAuthorComment (struct UsrData *UsrDat)
    bool ItsMe = Usr_ItsMe (UsrDat->UsrCod);
 
    /***** Start container *****/
-   fprintf (Gbl.F.Out,"<div class=\"TL_COM_AUTHOR TL_COMM_AUTHOR_WIDTH\">");
+   HTM_DIV_Begin ("class=\"TL_COM_AUTHOR TL_COMM_AUTHOR_WIDTH\"");
 
    /***** Show user's name inside form to go to user's public profile *****/
    Frm_StartFormUnique (ActSeeOthPubPrf);
@@ -3268,7 +3261,7 @@ static void TL_PutFormToShaUnsNote (const struct TL_Note *SocNot,
    bool IAmASharerOfThisSocNot;
 
    /***** Put form to share/unshare this note *****/
-   fprintf (Gbl.F.Out,"<div class=\"TL_ICO\">");
+   HTM_DIV_Begin ("class=\"TL_ICO\"");
    IAmTheAuthor = Usr_ItsMe (SocNot->UsrCod);
    if (SocNot->Unavailable ||		// Unavailable notes can not be shared
        IAmTheAuthor)			// I am the author
@@ -3398,7 +3391,7 @@ static void TL_PutFormToFavUnfNote (const struct TL_Note *SocNot,
    bool IAmAFaverOfThisSocNot;
 
    /***** Put form to fav/unfav this note *****/
-   fprintf (Gbl.F.Out,"<div class=\"TL_ICO\">");
+   HTM_DIV_Begin ("class=\"TL_ICO\"");
    IAmTheAuthor = Usr_ItsMe (SocNot->UsrCod);
    if (SocNot->Unavailable ||		// Unavailable notes can not be favourited
        IAmTheAuthor)			// I am the author
@@ -3566,7 +3559,7 @@ static void TL_PutFormToFavUnfComment (const struct TL_Comment *SocCom,
    bool IAmAFaverOfThisSocCom;
 
    /***** Put form to fav/unfav this comment *****/
-   fprintf (Gbl.F.Out,"<div class=\"TL_ICO\">");
+   HTM_DIV_Begin ("class=\"TL_ICO\"");
    IAmTheAuthor = Usr_ItsMe (SocCom->UsrCod);
    if (IAmTheAuthor)			// I am the author
       /* Put disabled icon */
@@ -4520,11 +4513,11 @@ static void TL_ShowUsrsWhoHaveSharedNote (const struct TL_Note *SocNot,
 				                                 TL_MAX_USRS_SHOWN);
 
    /***** Show users *****/
-   fprintf (Gbl.F.Out,"<div class=\"TL_NUM_USRS\">");
+   HTM_DIV_Begin ("class=\"TL_NUM_USRS\"");
    TL_ShowNumSharersOrFavers (SocNot->NumShared);
    HTM_DIV_End ();
 
-   fprintf (Gbl.F.Out,"<div class=\"TL_USRS\">");
+   HTM_DIV_Begin ("class=\"TL_USRS\"");
    TL_ShowSharersOrFavers (&mysql_res,SocNot->NumShared,NumFirstUsrs);
    if (NumFirstUsrs < SocNot->NumShared)
       TL_PutFormToSeeAllSharersNote (SocNot,HowMany);
@@ -4562,11 +4555,11 @@ static void TL_ShowUsrsWhoHaveMarkedNoteAsFav (const struct TL_Note *SocNot,
      }
 
    /***** Show users *****/
-   fprintf (Gbl.F.Out,"<div class=\"TL_NUM_USRS\">");
+   HTM_DIV_Begin ("class=\"TL_NUM_USRS\"");
    TL_ShowNumSharersOrFavers (SocNot->NumFavs);
    HTM_DIV_End ();
 
-   fprintf (Gbl.F.Out,"<div class=\"TL_USRS\">");
+   HTM_DIV_Begin ("class=\"TL_USRS\"");
    TL_ShowSharersOrFavers (&mysql_res,SocNot->NumFavs,NumFirstUsrs);
    if (NumFirstUsrs < SocNot->NumFavs)		// Not all are shown
       TL_PutFormToSeeAllFaversNote (SocNot,HowMany);
@@ -4602,11 +4595,11 @@ static void TL_ShowUsrsWhoHaveMarkedCommAsFav (const struct TL_Comment *SocCom,
 				                                 TL_MAX_USRS_SHOWN);
 
    /***** Show users *****/
-   fprintf (Gbl.F.Out,"<div class=\"TL_NUM_USRS\">");
+   HTM_DIV_Begin ("class=\"TL_NUM_USRS\"");
    TL_ShowNumSharersOrFavers (SocCom->NumFavs);
    HTM_DIV_End ();
 
-   fprintf (Gbl.F.Out,"<div class=\"TL_USRS\">");
+   HTM_DIV_Begin ("class=\"TL_USRS\"");
    TL_ShowSharersOrFavers (&mysql_res,SocCom->NumFavs,NumFirstUsrs);
    if (NumFirstUsrs < SocCom->NumFavs)
       TL_PutFormToSeeAllFaversComment (SocCom,HowMany);
@@ -4659,7 +4652,7 @@ static void TL_ShowSharersOrFavers (MYSQL_RES **mysql_res,
 	    /***** Get user's data and show user's photo *****/
 	    if (Usr_ChkUsrCodAndGetAllUsrDataFromUsrCod (&UsrDat,Usr_DONT_GET_PREFS))
 	      {
-               fprintf (Gbl.F.Out,"<div class=\"TL_SHARER\">");
+               HTM_DIV_Begin ("class=\"TL_SHARER\"");
 	       ShowPhoto = Pho_ShowingUsrPhotoIsAllowed (&UsrDat,PhotoURL);
 	       Pho_ShowUsrPhoto (&UsrDat,ShowPhoto ? PhotoURL :
 	                                             NULL,
diff --git a/swad_timetable.c b/swad_timetable.c
index ca162e07..06859fe0 100644
--- a/swad_timetable.c
+++ b/swad_timetable.c
@@ -232,7 +232,7 @@ static void TT_ShowTimeTableGrpsSelected (void)
    extern const char *Txt_Groups_OF_A_USER;
    extern const char *Txt_All_groups;
 
-   fprintf (Gbl.F.Out,"<div class=\"CLASSPHOTO_TITLE CM\">");
+   HTM_DIV_Begin ("class=\"CLASSPHOTO_TITLE CM\"");
    switch (Gbl.Crs.Grps.WhichGrps)
      {
       case Grp_MY_GROUPS:
@@ -1540,7 +1540,7 @@ static void TT_TimeTableDrawCell (unsigned Weekday,unsigned Interval,unsigned Co
 	 if (IntervalType != TT_FREE_INTERVAL) // If cell is not empty...
 	   {
 	    /***** Start cell *****/
-	    fprintf (Gbl.F.Out,"<div class=\"TT_CELL TT_TXT\">");
+	    HTM_DIV_Begin ("class=\"TT_CELL TT_TXT\"");
 
 	    /***** Course name *****/
 	    if (Gbl.TimeTable.Type == TT_MY_TIMETABLE)
diff --git a/swad_user.c b/swad_user.c
index 4da5785d..02dcabe3 100644
--- a/swad_user.c
+++ b/swad_user.c
@@ -2588,7 +2588,7 @@ void Usr_WriteFormLogin (Act_Action_t NextAction,void (*FuncParams) (void))
    extern const char *Txt_password;
 
    /***** Links to other actions *****/
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 
    Acc_PutLinkToCreateAccount ();
    Pwd_PutLinkToSendNewPasswd ();
@@ -2596,7 +2596,7 @@ void Usr_WriteFormLogin (Act_Action_t NextAction,void (*FuncParams) (void))
 
    HTM_DIV_End ();
 
-   fprintf (Gbl.F.Out,"<div class=\"CM\">");
+   HTM_DIV_Begin ("class=\"CM\"");
 
    /***** Begin form *****/
    Frm_StartForm (NextAction);
@@ -2608,7 +2608,7 @@ void Usr_WriteFormLogin (Act_Action_t NextAction,void (*FuncParams) (void))
                       Hlp_PROFILE_LogIn,Box_NOT_CLOSABLE,2);
 
    /***** User's ID/nickname *****/
-   fprintf (Gbl.F.Out,"<div class=\"LM\">");
+   HTM_DIV_Begin ("class=\"LM\"");
    fprintf (Gbl.F.Out,"<label for=\"UsrId\">"
                       "<img src=\"%s/user.svg\" alt=\"%s\" title=\"%s\""
 	              " class=\"CONTEXT_ICO_16x16\" />"
@@ -2626,7 +2626,7 @@ void Usr_WriteFormLogin (Act_Action_t NextAction,void (*FuncParams) (void))
    HTM_DIV_End ();
 
    /***** User's password *****/
-   fprintf (Gbl.F.Out,"<div class=\"LM\">");
+   HTM_DIV_Begin ("class=\"LM\"");
    fprintf (Gbl.F.Out,"<label for=\"UsrPwd\">"
                       "<img src=\"%s/key.svg\" alt=\"%s\" title=\"%s\""
 	              " class=\"CONTEXT_ICO_16x16\" />"
@@ -2812,8 +2812,7 @@ void Usr_WriteLoggedUsrHead (void)
    char PhotoURL[PATH_MAX + 1];
    unsigned NumAvailableRoles = Rol_GetNumAvailableRoles ();
 
-   fprintf (Gbl.F.Out,"<div class=\"HEAD_USR %s\">",
-	    The_ClassUsr[Gbl.Prefs.Theme]);
+   HTM_DIV_Begin ("class=\"HEAD_USR %s\"",The_ClassUsr[Gbl.Prefs.Theme]);
 
    /***** User's role *****/
    if (NumAvailableRoles == 1)
@@ -4122,7 +4121,7 @@ static void Usr_WriteUsrData (const char *BgColor,
 		 BgColor);
 
    /***** Container to limit length *****/
-   fprintf (Gbl.F.Out,"<div class=\"USR_DAT\">");
+   HTM_DIV_Begin ("class=\"USR_DAT\"");
 
    /***** Start link *****/
    if (Link)
@@ -6082,9 +6081,9 @@ void Usr_ShowFormsToSelectUsrListType (void (*FuncParams) (void))
    Set_StartOneSettingSelector ();
 
    /***** Select Usr_LIST_AS_CLASS_PHOTO *****/
-   fprintf (Gbl.F.Out,"<div class=\"%s\">",
-            Gbl.Usrs.Me.ListType == Usr_LIST_AS_CLASS_PHOTO ? "PREF_ON" :
-        	                                              "PREF_OFF");
+   HTM_DIV_Begin ("class=\"%s\"",
+		  Gbl.Usrs.Me.ListType == Usr_LIST_AS_CLASS_PHOTO ? "PREF_ON" :
+								    "PREF_OFF");
    Usr_FormToSelectUsrListType (FuncParams,Usr_LIST_AS_CLASS_PHOTO);
 
    /* Number of columns in the class photo */
@@ -6100,9 +6099,9 @@ void Usr_ShowFormsToSelectUsrListType (void (*FuncParams) (void))
    HTM_DIV_End ();
 
    /***** Select Usr_LIST_AS_LISTING *****/
-   fprintf (Gbl.F.Out,"<div class=\"%s\">",
-            Gbl.Usrs.Me.ListType == Usr_LIST_AS_LISTING ? "PREF_ON" :
-        	                                          "PREF_OFF");
+   HTM_DIV_Begin ("class=\"%s\"",
+		  Gbl.Usrs.Me.ListType == Usr_LIST_AS_LISTING ? "PREF_ON" :
+								"PREF_OFF");
    Usr_FormToSelectUsrListType (FuncParams,Usr_LIST_AS_LISTING);
 
    /* See the photos in list? */
@@ -7297,7 +7296,7 @@ void Usr_ListDataAdms (void)
       case Rol_CTR_ADM:
       case Rol_INS_ADM:
       case Rol_SYS_ADM:
-	 fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+	 HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 
 	 if (Gbl.Usrs.Me.Role.Logged == Rol_SYS_ADM)
 	   {
@@ -7352,7 +7351,7 @@ void Usr_ListDataAdms (void)
                  Hlp_USERS_Administrators,Box_NOT_CLOSABLE);
 
    /***** Form to select scope *****/
-   fprintf (Gbl.F.Out,"<div class=\"CM\">");
+   HTM_DIV_Begin ("class=\"CM\"");
    Frm_StartForm (ActLstOth);
    Usr_PutParamListWithPhotos ();
    fprintf (Gbl.F.Out,"<label class=\"%s\">%s:&nbsp;",
@@ -7365,8 +7364,8 @@ void Usr_ListDataAdms (void)
    if (Gbl.Usrs.LstUsrs[Rol_DEG_ADM].NumUsrs)
      {
       /****** Show photos? *****/
-      fprintf (Gbl.F.Out,"<div class=\"PREF_CONTAINER\">");
-      fprintf (Gbl.F.Out,"<div class=\"PREF_OFF\">");
+      HTM_DIV_Begin ("class=\"PREF_CONTAINER\"");
+      HTM_DIV_Begin ("class=\"PREF_OFF\"");
       Frm_StartForm (ActLstOth);
       Sco_PutParamCurrentScope ();
       Usr_PutCheckboxListWithPhotos ();
@@ -7793,7 +7792,7 @@ void Usr_SeeGuests (void)
    bool PutForm;
 
    /***** Put contextual links *****/
-   fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+   HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 
    /* Put link to remove old users */
    Usr_PutLinkToSeeAdmins ();
@@ -7826,7 +7825,7 @@ void Usr_SeeGuests (void)
    /***** Form to select scope *****/
    if (Gbl.Usrs.Me.Role.Logged == Rol_SYS_ADM)
      {
-      fprintf (Gbl.F.Out,"<div class=\"CM\">");
+      HTM_DIV_Begin ("class=\"CM\"");
       Frm_StartForm (ActLstGst);
       Usr_PutParamsPrefsAboutUsrList ();
       fprintf (Gbl.F.Out,"<label class=\"%s\">%s:&nbsp;",
@@ -7929,7 +7928,7 @@ void Usr_SeeStudents (void)
       case Rol_CTR_ADM:
       case Rol_INS_ADM:
       case Rol_SYS_ADM:
-         fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+         HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 
 	 /* Put link to go to admin student */
 	 Enr_PutLinkToAdminOneUsr (ActReqMdfOneStd);
@@ -7977,7 +7976,7 @@ void Usr_SeeStudents (void)
       case Rol_CTR_ADM:
       case Rol_INS_ADM:
       case Rol_SYS_ADM:
-	 fprintf (Gbl.F.Out,"<div class=\"CM\">");
+	 HTM_DIV_Begin ("class=\"CM\"");
 	 Frm_StartForm (ActLstStd);
 	 Usr_PutParamsPrefsAboutUsrList ();
 	 fprintf (Gbl.F.Out,"<label class=\"%s\">%s:&nbsp;",
@@ -8100,7 +8099,7 @@ void Usr_SeeTeachers (void)
       case Rol_CTR_ADM:
       case Rol_INS_ADM:
       case Rol_SYS_ADM:
-	 fprintf (Gbl.F.Out,"<div class=\"CONTEXT_MENU\">");
+	 HTM_DIV_Begin ("class=\"CONTEXT_MENU\"");
 
 	 /* Put link to go to admin one user */
 	 Enr_PutLinkToAdminOneUsr (ActReqMdfOneTch);
@@ -8155,7 +8154,7 @@ void Usr_SeeTeachers (void)
 		 Hlp_USERS_Teachers,Box_NOT_CLOSABLE);
 
    /***** Form to select scope *****/
-   fprintf (Gbl.F.Out,"<div class=\"CM\">");
+   HTM_DIV_Begin ("class=\"CM\"");
    Frm_StartForm (ActLstTch);
    Usr_PutParamsPrefsAboutUsrList ();
    fprintf (Gbl.F.Out,"<label class=\"%s\">%s:&nbsp;",
@@ -8953,7 +8952,7 @@ static void Usr_DrawClassPhoto (Usr_ClassPhotoType_t ClassPhotoType,
 			   ClassPhoto,Pho_ZOOM,false);
 
 	 /***** Photo foot *****/
-	 fprintf (Gbl.F.Out,"<div class=\"CLASSPHOTO_CAPTION\">");
+	 HTM_DIV_Begin ("class=\"CLASSPHOTO_CAPTION\"");
 
 	 /* Name */
 	 if (UsrDat.FirstName[0])
@@ -9713,9 +9712,8 @@ void Usr_WriteAuthor1Line (long UsrCod,bool Hidden)
 	             "PHOTO15x20",Pho_ZOOM,false);
 
    /***** Write name *****/
-   fprintf (Gbl.F.Out,"<div class=\"AUTHOR_1_LINE %s\">",
-            Hidden ? "AUTHOR_TXT_LIGHT" :
-        	     "AUTHOR_TXT");
+   HTM_DIV_Begin ("class=\"AUTHOR_1_LINE %s\"",Hidden ? "AUTHOR_TXT_LIGHT" :
+        	                                        "AUTHOR_TXT");
    fprintf (Gbl.F.Out,"%s",UsrDat.FullName);
    HTM_DIV_End ();