Thank you for the feedback.
I was not able to reproduce triggering the click event of the button, however I noticed another issue - the textarea under the first DropDownList gets selected after the widget closes. I spoke with the developer team and they confirmed the problem. Currently we are making changes in the implementation in order to avoid this behaviour. The fix should be available within a few days. I will attach it to the bug report ticket that you submitted as soon as it is ready.
Once again I apologize for the inconvenience caused.
the Telerik team
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