Index: lams_build/conf/etherpad/etherpad-lite/node_modules/ep_comments_page/static/js/index.js
===================================================================
diff -u -rf9dafe60150e1899c37200977b198e0546ced60c -r7ba9b61ebdd7931c2db2078f365b10f2b9c776ad
--- lams_build/conf/etherpad/etherpad-lite/node_modules/ep_comments_page/static/js/index.js	(.../index.js)	(revision f9dafe60150e1899c37200977b198e0546ced60c)
+++ lams_build/conf/etherpad/etherpad-lite/node_modules/ep_comments_page/static/js/index.js	(.../index.js)	(revision 7ba9b61ebdd7931c2db2078f365b10f2b9c776ad)
@@ -344,6 +344,7 @@
   // LAMS modifies this logic so right comments bar is hidden by default
   $('#options-comments').prop('checked', padcookie.getPref('comments') === true);
 
+
   $('#options-comments').on('change', () => {
     const checked = $('#options-comments').is(':checked');
     padcookie.setPref('comments', checked);
@@ -883,9 +884,12 @@
     rep.lines = saveRep.lines;
     rep.selStart = saveRep.selStart;
     rep.selEnd = saveRep.selEnd;
+    rep.hasCommentsOnSelection = ace.ace_hasCommentOnSelection();
   }, 'saveCommentedSelection', true);
 
+
   const selectedText = this.getSelectedText(rep);
+
   // we have nothing selected, do nothing
   const noTextSelected = (selectedText.length === 0);
   if (noTextSelected) {
@@ -896,6 +900,14 @@
     return;
   }
 
+  //LAMS modification: prevent comments from being overwritten
+  if (rep.hasCommentsOnSelection) {
+	$.gritter.add({
+	  text: 'This text already has a comment. Reply on the existing comment instead.'
+	});
+	return;
+  }
+
   this.createNewCommentFormIfDontExist(rep);
 
   // Write the text to the changeFrom form