I have already replied to your support ticket on the same subject. I will repeat the answer here as well, so the other users who experience the same behaviour would be able to read it.
Indeed the problem occurs only if alert is used and cannot be reproduced if for example console.log()
is called instead. It seems that the alert call is actually causing that issue itself, because the event did not fire twice in any other case that we tested.
the Telerik team
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