Last Updated: 01 Sep 2014 07:42 by ADMIN
Last Updated: 01 Mar 2017 13:45 by Warren
Last Updated: 06 Nov 2019 14:48 by ADMIN
Release R2 2018
Possible Workaround:

Telerik.Web.UI.Grid.PositionDragElement = function(element, mouseEvent)
    var clientX = $telerik.isTouchDevice ? $telerik.getTouchEventLocation(mouseEvent).x : mouseEvent.clientX;
    var clientY = $telerik.isTouchDevice ? $telerik.getTouchEventLocation(mouseEvent).y : mouseEvent.clientY; = clientY + $telerik.getDocumentElementScrollTop() + 10 + "px"; = clientX + $telerik.getDocumentElementScrollLeft() + 10 + "px";

	if ($telerik.isOpera || $telerik.isTouchDevice)
	{ = parseInt(, 10) - document.body.scrollTop + "px";

Last Updated: 18 Jun 2015 19:55 by Clyde
Under IE, when two tables are placed next to each other, the Table Properties may cause the one to appear nested inside.

Currently, this can be workarounded only by assuring that there is some element between them - <br>, <p>, <div>, <span> etc.
Last Updated: 18 Feb 2015 09:30 by ADMIN
Last Updated: 13 Oct 2014 13:46 by ADMIN
Last Updated: 03 Nov 2015 11:47 by Asad
System.Exception: 453.6 is not a valid value for Int32.
Last Updated: 28 Jun 2019 11:02 by ADMIN
Last Updated: 19 Aug 2019 12:26 by ADMIN
Last Updated: 20 Mar 2019 11:13 by ADMIN
Created by: Petar
Comments: 3
Category: UI for ASP.NET AJAX
Type: Bug Report

Last Updated: 10 Oct 2013 15:38 by ADMIN
If the body tag of the content area of RadEditor has applied font-size with em and line-height attribute in Chrome, the contents of the produced ordered/undoreded lists will be wrapped in a span tag with this formatting.

Steps to reproduce:
1) Put the following CSS on the page
			font-size: 0.875em; 
			line-height: 10.4px; 

2) Load this content in RadEditor
line1<br />
line2<br />

3) Select the three lines in Design mode and press the InsertUnorederedList button. The produced content in Google Chrome will be
    <li><span style="font-size: 0.875em; line-height: 10.4px;">line1</span></li>
    <li><span style="font-size: 0.875em; line-height: 10.4px;">line2</span></li>
    <li><span style="font-size: 0.875em; line-height: 10.4px;">line3</span></li>

instead of the expected one:

Note: This is a WebKit browser behavior which can be reproduced by firing the browser's execCommand method with the InsertOrderedList command identifier:

Last Updated: 30 Sep 2014 15:13 by ADMIN
The problem is due to the IE native focusing behavior of editable DIV elements. 

You can workaround this problem by overriding the setFocus method and implement an if statement that does not focus the content if the  AutoResizeHeight is enabled:

<telerik:RadEditor ID="RadEditor1" runat="server" AutoResizeHeight="True" ContentAreaMode="Div">

<script type="text/javascript">
	Telerik.Web.UI.RadEditor.prototype.setFocus = function () {
		try {
			if ($telerik.isIE && this.getSelection().isControl()) return;

			var area = this.get_mode() != $T.EditModes.Html ? this.get_contentWindow() : this._getTextArea();
			if (this.get_contentAreaMode() == $T.EditorContentAreaMode.Div) area = this.get_contentArea();
			if (area && area.focus && !this.get_autoResizeHeight()) area.focus();
		catch (e) { }

Last Updated: 04 Dec 2017 09:54 by Anatoliy
Created by: Rumen
Comments: 3
Category: UI for ASP.NET AJAX
Type: Bug Report

With the latest version of Chrome 61 the context menu is not positioning correctly in the treeview. It only happens when the treeview is longer than the window height and there are scrollbars. The EnableScreenBoundaryDetection should be enabled too (it is enabled by default).

Reproduction: see this video for a repro The problem does not happen in the Chrome versions prior 61.

Details and Resolution: 

The context menu positioning problem is due to the following breaking change in Chrome 61 (see release notes at

To align with the spec and preserve browser consistency, the scrollingElement is now the documentElement in standards mode.
Chrome 61 has changed the behavior of document.scrollingElement to return document.documentElement instead of document.body to match the CSSOM View specification and this broke the positioning of the context menu when the EnableScreenBoundaryDetection is enabled.

Solution 1
Place the following override over the RadTreeView declaration:

Telerik.Web.UI.RadMenu._getViewPortSize = function () {
        var viewPortSize = $telerik.getViewPortSize();
        // The document scroll is not included in the viewport size
        // calculation under FF/quirks and Edge.     
        var quirksMode = document.compatMode != "CSS1Compat";
        if (($telerik.isFirefox && quirksMode) || Telerik.Web.Browser.edge) {
            viewPortSize.height += document.body.scrollTop;
            viewPortSize.width += document.body.scrollLeft;
        else if ( {
            viewPortSize.height += Math.max(document.body.scrollTop, document.scrollingElement.scrollTop);
            viewPortSize.width += Math.max(document.body.scrollLeft, document.scrollingElement.scrollLeft);
        return viewPortSize;
<telerik:RadTreeView RenderMode="Lightweight" ID="RadTreeView2" runat="server">
        <telerik:RadTreeViewContextMenu ID="RadTreeViewContextMenu1"runat="server"  RenderMode="Lightweight">

Solution 2
Set EnableScreenBoundaryDetection to false. This will disable the screen boundary detection and some parts of the context menu could be rendered beneath the browser borders when there isn't enough space to be rendered on the visible screen. You will have to use the browser scrollbars to show the hidden part of the menu.

The issue is scheduled for fixing in R3 2017 SP1, the release date of which is not yet decided. Please use the provided solutions above until the SP1 goes out officially.
Last Updated: 17 Apr 2018 11:53 by Raymond
There are two ways to avoid this:

- Define a tab order on the entire page so all necessary controls will have their TabIndex attribute set

- Remove the attribute from the menu with JS. Here follow a couple of examples. Using RenderMode="Lightweight" also may improve the situation if you do not use the NavigateUrl of the items, so <a> elements are not rendered.

     - Solution 1: Executes when the entire page has loaded
               function removeMenuTabIndex() {

     - Solution 2: Add just after the menu so it executes while the DOM is loading, perhaps this can facilitate screen reader compatibility

        <telerik:RadMenu runat="server" ID="rm1" RenderMode="Lightweight">
                    <telerik:RadMenuItem Text="first"></telerik:RadMenuItem>
                    <telerik:RadMenuItem Text="second"></telerik:RadMenuItem>
Last Updated: 25 Apr 2017 15:30 by rleast
Last Updated: 28 Nov 2018 15:29 by ADMIN
Can be reproduced with the following page setup:

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="Default" %>
<%@ Register Assembly="Telerik.Web.UI" Namespace="Telerik.Web.UI" TagPrefix="telerik" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "">

<html xmlns="">
<head runat="server">

    <form id="form1" runat="server">
    <telerik:RadScriptManager ID="RadScriptManager1" runat="server">

    <div style="height:930px">
        Scroll down to bottom of the page and right mouse click to see context menu miss placement....
        <telerik:RadEditor RenderMode="Classic" ID="redHtmlEditor" runat="server" 
                    Right-click on image to see custom menu
                    <img style="marign-left: 6px" src="" />
                    <p>Right-click here to see the custom Paragraph menu.<br/></p><br/>           
                    Right-click on the link to see the default link menu disabled: <a href="/"></a>   

Last Updated: 17 Mar 2015 14:32 by ADMIN
Last Updated: 09 Mar 2015 06:28 by ADMIN
Created by: Daniel
Comments: 0
Category: UI for ASP.NET AJAX
Type: Bug Report
Ticket # 541004
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