Currently the RadButton control does not provide an access to its click DOM event object. This is a good suggestion and it will be brought to the attention of our developers for future implementation. Here
you can track the status of the feature request in PITS.
For the time being you can use the following workaround to get the DOM event, which is contained in the variable domEvent
Telerik.Web.UI.RadButton.prototype._mouseClickHandlerOld = Telerik.Web.UI.RadButton.prototype._mouseClickHandler;
domEvent = args.rawEvent;
I have updated your telerik points accordingly as a token of gratitude for your suggestion.
the Telerik team
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