This is such a timewaster. Click the wrong item in the pulldown list, and
you have just wasted 10 minutes.
Of course, the work around is to kill the Idea process from the OS, but it
doesn't "feel right".
BTW, the issue is not new - it was raised in http://www.intellij.net/tracker/idea/viewSCR?publicId=23585
on Dec 14, 2003.
With each point release I hope for the little magic "Cancel" button, but
it's not there. This is such a basic UI requirement,
that I'm amazed it has been ignored for so long.