Thank you for the writing.
I tested a case similar to yours, but I was not able to reproduce the described behavior. This most probably means that you have outdated display drivers. The only thing I can suggest is to try this on another machine with different video card or with updated video drivers.
If you experience the issue on the other machine, please send me the project. This will allow me to debug the case locally and provide you with further assistance.
I hope this helps.
All the best,
the Telerik team
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