Thank you for contacting us.
I’ve tried to reproduce the issue you are experiencing with the missing image of Image Button on our live demos but no avail.
I'm also attaching a video demonstrating the test.
If you continue to experience the issue, please provide us with more information and simple, fully runnable project so that we will be able to examine it locally and if we are missing something in order to recreate your scenario.
All the best,
the Telerik team
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