Last Updated: 02 Nov 2020 15:50 by ADMIN
Release R1 2021
Created on: 02 Nov 2020 08:13
Category: Window
Type: Bug Report
Window titlebar gets flatten in Bootstrap

When using Telerik controls with Bootstrap theme and Bootstrap 3.x the radWindow title has cosmetic issue (see attached).

It appeared that Bootstrap global box-sizing: border-box is the reason. 

Repro markup:

<!DOCTYPE html>

<html xmlns="">
<head runat="server">
    <!-- Latest compiled and minified CSS -->
    <link rel="stylesheet" href="" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">

    <!-- Optional theme -->
    <link rel="stylesheet" href="" integrity="sha384-rHyoN1iRsVXV4nD0JutlnGaslCJuC7uwjduW9SVrLvRYooPp2bWYgmgJQIXwl/Sp" crossorigin="anonymous">

    <!-- Latest compiled and minified JavaScript -->
    <script src="" integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa" crossorigin="anonymous"></script>
    <form id="form1" runat="server">
        <asp:ScriptManager runat="server" />

        <telerik:RadWindow Skin="Bootstrap" ID="RadWindow1" runat="server" Title="Some RadWindow title" VisibleOnPageLoad="true" RenderMode="Lightweight">

Bootstrap skin 

Silk skin

The workaround is to set box-sizing: content-box in rwTitleWrapper:

       box-sizing: content-box !important;


1 comment
Posted on: 02 Nov 2020 08:22

Hi everyone,

We will fix this issue with priority for R1 2021. 

The provided workaround is applicable for the old versions too:

       box-sizing: content-box !important;

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