I have an IFrame in my CRM 2011 on-premises with the following settings:
URL: about:blank
Pass record object-type code and unique identifier as parameter: NOT checked
Restrict cross-frame scripting, where supported: NOT checked
Visible by default: checked
Event: OnReadyStateComplete, Function = SetURL, Enabled = checked
However, when I open the account OnReadyStateComplete never fires. I also changed the function name to SetURL1 (which does not exist) but there is no error. When I click in the IFrame and select Properties I see that the URL is set to about:blank, i.e. the initial URL. Why does OnReadyStateComplete not fire and how can I get it to fire?