This is a problem with the "Find on this page" dialog which is present in the Win32 M12 release, found when running Windows NT. Reproduction instructions: 1. Load open a web site, (And site it doesn't matter). 2. Click "Search : Find on this Page". 3. Click "Cancel" 4. Click on the main Mozilla window. 5. Mozilla crashes, with an access violation. Interestingly Mozilla doesn't do this if you click on the "x" (Close window icon), rather than on the Cancel button. The error appears to be in gkhtml.dll, (in my copy the crash address is 6022cec8 - but thats probably meaningless). I've just downloaded the source so I'll see if I get it built and narrow down the problem.

QA Assigning to Claudius, who probably knows which engineer should get this.

This is fixed in the M13 nightly builds. See, for example, bug 22234. *** This bug has been marked as a duplicate of 22360 ***

*** Mark verified as duplicate of 22360 ***