HowTo: Tell IE to use compatibility mode without editing your web pageshttps://www.dotnetzone.gr:443/cs/blogs/birbilis/archive/2014/08/22/howto-tell-ie-to-use-compatibility-mode-without-editing-your-web-pages.aspxat http://www.mono-software.com/Mono/Pages/Discussion/dtopic/_YyUBIlx5kiqHaNqAQeltg/br-brake-bug-in-IE11-and-clipflair-text-editor/ one reads: We are using Telerik’s rich text editor (RadEditor), and it seems that RadEditor has specific behaviourelCommunityServer 2.1 SP3 (Build: 20423.1)