I have just tested the project attached in the KB article with the Q1 2013 release (2013.1.220) and it appears to be working fine with me. For your convenience I am attaching it here as well, together with a short video from my test. Can you confirm if this is working as expected on your end? If not - can you locate the difference with your actual case - e.g. larger images being used, some error being thrown, the page having invalid markup or doctype, etc.? If taking the approach used in the sample still does not work for you can you post the code that is actually causing issues with you so I can check it?
the Telerik team
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