Hi Martin,
It seems that Google Maps API is using Strict Mode and apparently MSAjax is not compatible with it - the error thrown originates from the __doPostBack() function.
A possible workaround would be to wrap the ajaxRequest() call in a setTimeout, however, this will move the the execution outside of the current scope and might not work for this scenario but I was unable to find another approach to overcome the strict mode.
Regards,
Dobromir
Telerik
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