I tested the hovered RadButton behavior under several browsers, but I wasn't able to reproduce the reported problem, as you can check in this screen capture
. I have also added my test project so that you can compare it with yours and verify that my setup matches yours. Please let us know if you are encountering the described behavior in the attached sample as well.
Most probably the reported problem is caused by your browser installation, so you could try resetting and even reinstalling the browser under which the flickering occurs. Any additional information about your scenario will help us much in inspecting the issue - is it reproducible on other machines, under which browser you have encountered it, which version of the RadControls for ASP.NET AJAX are you using, is there anything specific about your page or the image blinking occurs even on a simple page, containing only a RadButton.
Note that at the current state of affairs I am mostly guessing as to what your setup is and if you are still experiencing difficulties please try modifying the attached project so that the reported behavior is reproducible or prepare and send a simple, runnable page
that displays your issue so that we can examine it locally and provide a more to the point answer.
All the best,
the Telerik team
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