Thank you for the provided video. The reason is most likely related to your page/application not handling encoding properly. By default ASP.NET applications use utf-8 encoding, as specified in the Web.config. As far as sending symbols back and forth the server the editor is not doing almost anything in particular.
The only cases where we have been reported problematic behavior is when either the encoding in the Web.config is changed, or alternatively, the database field that is used to save the content is not utf/Unicode.
My suggestion is to test make sure your application uses utf encoding and see how it works. In case you are not able to resolve the problem in a satisfactory way, we will need you to open a support ticket and send us a simple, yet fully functional project for us to reproduce the problem. Once we do so on our end we will quickly get back to you with what setting exactly is causing it as well as suggestions how to get things working.
the Telerik team
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