When EnableComments is set to true, the content from the clipboard is pasted twice in an empty editor.

RadEditor Configuration:

<telerik:RadEditor runat="server"
    EnableComments="true">
    <Tools>
        <telerik:EditorToolGroup>
            <telerik:EditorTool Name="Bold" />
            <telerik:EditorTool Name="Italic" />
            <telerik:EditorTool Name="Underline" />
            <telerik:EditorSeparator />
            <telerik:EditorTool Name="Undo" />
            <telerik:EditorTool Name="Redo" />
            <telerik:EditorTool Name="Cut" />
            <telerik:EditorTool Name="Copy" />
            <telerik:EditorTool Name="Paste" />
            <telerik:EditorTool Name="PastePlainText" Text="Paste Plain Text" />
            <telerik:EditorTool Name="FindAndReplace" Text="Find and Replace" />
            <telerik:EditorSeparator />
            <telerik:EditorTool Name="Indent" />
            <telerik:EditorTool Name="Outdent" />
            <telerik:EditorTool Name="InsertOrderedList" Text="Numbered List" />
            <telerik:EditorTool Name="InsertUnorderedList" Text="Bulleted List" />
            <telerik:EditorTool Name="LinkManager" />
            <telerik:EditorTool Name="Unlink" />
            <telerik:EditorSeparator />
            <telerik:EditorTool Name="AjaxSpellCheck" Text="Spell Check" />
            <telerik:EditorTool Name="InsertSymbol" Text="Insert Symbol" />
        </telerik:EditorToolGroup>
        <telerik:EditorToolGroup>
            <telerik:EditorTool Name="AcceptTrackChange" Text="Accept Change" />
            <telerik:EditorTool Name="RejectTrackChange" Text="Reject Change" />
            <telerik:EditorTool Name="AcceptAllTrackChanges" Text="Accept All Changes" />
            <telerik:EditorTool Name="RejectAllTrackChanges" Text="Reject All Changes" />
            <telerik:EditorTool Name="EnableTrackChangesOverride" Text="Track Changes" />
            <telerik:EditorTool Name="AddComment" Text="Add Comment" />
            <telerik:EditorTool Name="RemoveComment" Text="Remove Comment" />
            <telerik:EditorTool Name="RemoveAllComments" Text="Remove All Comments" />
            <telerik:EditorTool Name="ImageManager" Text="Insert Image" />
        </telerik:EditorToolGroup>
    </Tools>
</telerik:RadEditor>

Potential workaround:
<script type="text/javascript">
    function OnClientPasteHtml(sender, args) {
        var commandName = args.get_commandName();
        var value = args.get_value();
 
        if (commandName == "Paste" && Telerik.Web.Browser.ie) {
            args.set_value(value);
            args.set_cancel(true);
        }
    }
</script>
<telerik:RadEditor runat="server" Height="300px" StripFormattingOptions="Span,Font,Css" EnableTrackChanges="true" OnClientPasteHtml="OnClientPasteHtml"
    ContentFilters="FixEnclosingP,RemoveScripts,FixUlBoldItalic,IECleanAnchors,MozEmStrong,ConvertFontToSpan,ConvertToXhtml,IndentHTMLContent,EncodeScripts,OptimizeSpans,ConvertTags,StripCssExpressions,RemoveExtraBreaks"
    EnableComments="true" NewLineMode="P" EditModes="Design,Html">
</telerik:RadEditor>

When using the Microsoft Edge browser with the Editor, you cannot add field values for some form elements. This seems to affect Radio buttons and checkboxes. It is possible that it affects other form elements as well. I also see this same problem when using your demo page https://demos.telerik.com/aspnet-ajax/editor/examples/overview/defaultcs.aspx.

Edge does not offer the hasLayout capability of Internet Explorer, which selects the form element on click. In Edge you can select a form element as you could do it with a text: https://www.screencast.com/t/mo25Rm1kTSdB. The click selection is not currently supported.

Steps to reproduce:
1. Go to the Editor demo page in Chrome
2. CTRL+A on the editor and hit delete
3. Hit Delete or Backspace again
Result: Uncaught TypeError Appears in the console

When RadEditor is configured with RenderMode="Auto", it renders fine on a mobile, but the Find and Replace throws a JavaScript error:

Uncaught Error: Sys.ArgumentNullException: Dialog Parameters for the FindAndReplace dialog do not exist

Parameter name: dialogName
    at Function.Error$create [as create] (ScriptResource.axd?d=drtcXVcvAjvxxGTIp4ks_jsffAtTgDZa7F-xsErOE7x83oPLnSroIDP2Rlpln027LL6pHm8wDFlVd2TfNwyX9tsTD0IfApyfv4p2GRpAUsfag9bRTF3ZhqYQPg2KFASuXMmfKVcURGhOxnF7S60OLuj9cWAWD2oOw-AOIsKJVpoN8aJcHQVfLpfuW8e9J_z70&t=74693645:237)
    at Function.Error$argumentNull [as argumentNull] (ScriptResource.axd?d=drtcXVcvAjvxxGTIp4ks_jsffAtTgDZa7F-xsErOE7x83oPLnSroIDP2Rlpln027LL6pHm8wDFlVd2TfNwyX9tsTD0IfApyfv4p2GRpAUsfag9bRTF3ZhqYQPg2KFASuXMmfKVcURGhOxnF7S60OLuj9cWAWD2oOw-AOIsKJVpoN8aJcHQVfLpfuW8e9J_z70&t=74693645:279)
    at b.RadDialogOpener._getDialogDefinition (ScriptResource.axd?d=CcXTXAXm_2uXk6i-z8e-9-GUON7JgJld7fON2waeoUCDG-568SfljYE0OxAYq5S_l1j5QbPdt7yR5Ji7ARrlqe9xsoWPpTVgVVnsC2r0rN-hCMOIKe3sXa-glZDwstuHDCKnEGv03WuBZg3A1mEmGb3cZzVnLPok8zmI9TSFWuc1&t=6e6e42a6:199)
    at b.RadDialogOpener.open (ScriptResource.axd?d=CcXTXAXm_2uXk6i-z8e-9-GUON7JgJld7fON2waeoUCDG-568SfljYE0OxAYq5S_l1j5QbPdt7yR5Ji7ARrlqe9xsoWPpTVgVVnsC2r0rN-hCMOIKe3sXa-glZDwstuHDCKnEGv03WuBZg3A1mEmGb3cZzVnLPok8zmI9TSFWuc1&t=6e6e42a6:65)
    at c.RadEditor.showDialog (ScriptResource.axd?d=wYaAc3J2NgVJCu2P39J4xyGaoOdrMcpsgItEXwZ_xZ-mxwwqth9gFwZgQmz64y0L50bOGm0jxdnTOv_b92sCumvlnrhdNCqVSpfDTXuridpdeelSxC1ktLGb8SRXNUQSfAkHpn5XxFbvggex9gxJzw2&t=6e6e42a6:8753)
    at Telerik.Web.UI.Editor.CommandList.FindAndReplace (ScriptResource.axd?d=wYaAc3J2NgVJCu2P39J4xyGaoOdrMcpsgItEXwZ_xZ-mxwwqth9gFwZgQmz64y0L50bOGm0jxdnTOv_b92sCumvlnrhdNCqVSpfDTXuridpdeelSxC1ktLGb8SRXNUQSfAkHpn5XxFbvggex9gxJzw2&t=6e6e42a6:5051)
    at c.RadEditor.fire (ScriptResource.axd?d=wYaAc3J2NgVJCu2P39J4xyGaoOdrMcpsgItEXwZ_xZ-mxwwqth9gFwZgQmz64y0L50bOGm0jxdnTOv_b92sCumvlnrhdNCqVSpfDTXuridpdeelSxC1ktLGb8SRXNUQSfAkHpn5XxFbvggex9gxJzw2&t=6e6e42a6:9266)
    at c.RadEditor._onToolClick (ScriptResource.axd?d=wYaAc3J2NgVJCu2P39J4xyGaoOdrMcpsgItEXwZ_xZ-mxwwqth9gFwZgQmz64y0L50bOGm0jxdnTOv_b92sCumvlnrhdNCqVSpfDTXuridpdeelSxC1ktLGb8SRXNUQSfAkHpn5XxFbvggex9gxJzw2&t=6e6e42a6:8619)
    at Array.<anonymous> (ScriptResource.axd?d=drtcXVcvAjvxxGTIp4ks_jsffAtTgDZa7F-xsErOE7x83oPLnSroIDP2Rlpln027LL6pHm8wDFlVd2TfNwyX9tsTD0IfApyfv4p2GRpAUsfag9bRTF3ZhqYQPg2KFASuXMmfKVcURGhOxnF7S60OLuj9cWAWD2oOw-AOIsKJVpoN8aJcHQVfLpfuW8e9J_z70&t=74693645:47)
    at ScriptResource.axd?d=drtcXVcvAjvxxGTIp4ks_jsffAtTgDZa7F-xsErOE7x83oPLnSroIDP2Rlpln027LL6pHm8wDFlVd2TfNwyX9tsTD0IfApyfv4p2GRpAUsfag9bRTF3ZhqYQPg2KFASuXMmfKVcURGhOxnF7S60OLuj9cWAWD2oOw-AOIsKJVpoN8aJcHQVfLpfuW8e9J_z70&t=74693645:3484

Render mode configuration in the web.config

<add key="Telerik.Web.UI.RenderMode" value="Auto" />
It seems, code is looking for FindAndReplace key in this._dialogDefinitions, but it's not there. However, the key FindAndReplaceSettings is there.

We have an issue where the RadEditor context menu for <td> element doesn't get displayed. It throws a "Permission Denied" error. Within <td> the table toolbar is not functional either. 
To reproduce: In an aspx page, create an updatepanel with a LoadContent button, RadEditor and Save button.
1. Click on Load Contents button
2. RadEditor with text "Loaded" will get displayed
3. Insert a table
4. Go to a table cell and verify context menu for td shows fine
5. Click Save
6. Go to a table cell and right click - context menu doesn't show (If you have IE developers tool, you will see "Permission Denied" error.)

ASPx page:
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="server">
    <asp:UpdatePanel ID="upd" runat="server">
        <ContentTemplate>
              <asp:Button ID="btnLoad" runat="server" Text="Load Contents"  OnClick="btnLoad_Click"  />
              <telerik:RadEditor ID="HTMLEditor" runat="server"></telerik:RadEditor>          
                <asp:Button ID="btnSave" runat="server" Text="Save"  OnClick="btnSave_Click" UseSubmitBehavior="false" />
        </ContentTemplate>
    </asp:UpdatePanel>     
</asp:Content>
C# Code:
 protected void Page_Load(object sender, EventArgs e)
        {
        }
        protected void btnSave_Click(object sender, EventArgs e)
        { 
            HTMLEditor.Content = HTMLEditor.Content + " updated";            
        }
        protected void btnLoad_Click(object sender, EventArgs e)
        {
            HTMLEditor.Content = "Loaded";
        }

Content font famility is changed when a word is spell checked in Chrome in Windows 7.

Video: https://www.screencast.com/t/Y358IWoWz

Steps to reproduce:

Paste the following content in this demo: http://demos.telerik.com/aspnet-ajax/editor/examples/overview/defaultcs.aspx

<span id="ctl10_supportMessagesRepeaterControl_repeaterMessages_ctl11_lblMessageText" class="text"><span style="font-family: Arial; font-size: small; background-color: #ffffff;">Dear Telerik&nbsp;</span><br style="font-family: Arial; font-size: small; background-color: #ffffff;" />
<br style="font-family: Arial; font-size: small; background-color: #ffffff;" />
<strong>Notice: Issue: 2016: WestenBook Help and Test<br />
Please check it 20170828 &nbsp;</strong><span style="font-family: Arial; font-size: small; background-color: #ffffff;"></span></span>

When the fore/backcolor of the Editor is changed through its toolbar, the same color is set to all Editors on the page. The problem is reproducible in Lightweight rendering.

Video: https://www.screencast.com/t/YQ4OnNmu

http://demos.telerik.com/aspnet-ajax/editor/examples/overview/defaultcs.aspx
Clear content;
Add a table;
Open context menu by selecting a cell in the table;
Open Cell Properties;
Open More cell Styling;
Chose Background color;
Change it and click OK
Click OK in Table Wizard.
Actual: No background color is applied. 

Even if the ToolsFile is pointing to a valid file, no toolbar is rendered when the control is loaded in a mobile browser.


Run the following code in Chrome's mobile emulator:
<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>RadEditor Mobile Toolbar Vanishing</title>
   <meta name="viewport" content="width=device-width, initial-scale=1.0,maximum-scale=1.0, user-scalable=no"/>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <asp:ScriptManager ID="ScriptManager1" runat="server"></asp:ScriptManager>
        <telerik:RadEditor ID="RadEditor1" runat="server" RenderMode="Auto" ToolsFile="toolsFile.xml"></telerik:RadEditor>
    </div>
    </form>
</body>
</html>

ImageManager's layout is broken in Bootstrap in Lightweight:
https://www.screencast.com/t/Sdu2XbqVh11b

Steps to reproduce:
1. Open http://demos.telerik.com/aspnet-ajax/editor/examples/overview/defaultcs.aspx?skin=Bootstrap

2. Open the ImageManager dialog

I recently updated my website with the dll patch telerik  provided for the cryptographic weakness:
http://www.telerik.com/support/kb/aspnet-ajax/details/cryptographic-weakness?utm_medium=email

After the update I found that the pages which were using the RadEditor control and several other controls was not loading and throwing this error:
Parser Error Message: Decryption key specified has invalid hex characters.

Several other controls are throwing this error but I cannot delete controls one by one and check which ones are having this problem.

But I checked for the RadEditor and it was throwing this error. Nothing else is there on the page while testing other than this control.
This does not happen on a plain new website and is happening when we have the sql mermbership and machine key configured. We are using passwordFormat as encrypted in sql membership config and cannot remove machine key.
If you got to test it, then test it on some already configured machine key and sql membership website.

I have attached screenshots for this error and telerik dll patch in use currently.

We are on a production server and we need a solution for this issue ASAP.

The Edit Content and other toolbar buttons are untouchable on Android Chrome on Galaxy S7, S8 and Note 5.

It is very hard to switch to edit mode and so on.
http://demos.telerik.com/aspnet-ajax/editor/examples/mobile-and-touch-support/adaptive-behavior/defaultcs.aspx

 Out of stack space error is thrown by the Find & Replace dialog in IE11/Edge when there is an img tag withing the content. The image will cause the Find feature to sit and spin when searching for a string after the img tag. It does not return a result and it does not trigger a modal to display, e.g., “The search string was not found.”

Pressing ENTER over a list item not only creates a new li, but also inserts additional <br> element.

Video: https://www.screencast.com/t/PZcYTKEtY4v

Steps to reproduce:
1. Open in Chrome:
2. Switch to Html mode and insert the following content:
<ol>
    <li>123 456
    <ol>
        <li>abc</li>
    </ol>
    </li>
    <li>789</li>
</ol>

3. Switch to design mode
4. Put the cursor inside the first li (e.g. before 5) and press ENTER

Result: A <br> element is added in the beginning of the new <li> element

Deleting the fisrt char of a list item removes the li element instead of the char (using Delete button). 

The issue is introduced in Q1 2016.


Steps to reproduce:
1. Open http://demos.telerik.com/aspnet-ajax/editor/examples/overview/defaultcs.aspx
2. Insert the following content in html mode:
 <ol>
    <li>123</li>
    <li>456</li>
</ol>

3. Switch to Design mode and click in the begining of the second list item (befor 4).
4. Press the Delete key

Result:
<ol>
    <li>123456</li>
</ol>

Expected
 <ol>
    <li>123</li>
    <li>56</li>
</ol>

You can create a list item, but it is impossible to type text in the list item.

Toolbar icons are missing in Image Manager dialog when custom content provider is used
https://www.screencast.com/t/VQyEb8tn

The Properties tab in Image Manager dialog Preview tab appear as blank when custom content provider is used.

RadEditor strips urls pointing to the current page when MakeUrlsAbsolute is enabled.

Steps to reproduce:
1. Open http://demos.telerik.com/aspnet-ajax/editor/examples/builtincontentfilters/defaultcs.aspx

2. Clear the content of the Editor, swith to html mode and paste the following content:
test
<a href="http://demos.telerik.com/aspnet-ajax/editor/examples/builtincontentfilters/defaultcs.aspx" target="_self">2.2.2</a>
<br>
<table bordercolor="#000000" border="1" cellspacing="0" cellpadding="2">
    <tbody>
        <tr>
            <td style="text-align: center; vertical-align: middle;" rowspan="2"><strong>Text</strong></td>
        </tr>
    </tbody>
</table>


3. Switch to Design mode and back to html mode.

Result: The content will be stripped like follows:
test
<a href="#000000" border="1" cellspacing="0" cellpadding="2">
     
         
            <strong>Text</strong>
         
     
</a>

Occurs in IE11, IE10, or IE9 (Works in IE8).
Copy a table from MS word/excel into editor.
Right-click right most column.
Select Column > Delete Column.
Unable to select other rows in copied table or edit table cells