Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:13.0a1) Gecko/20120208 Firefox/13.0a1 1. Open Firefox. 2. Select View-Full Screen. Actual result: no action is performed. Firefox does not enter full screen. This regressed following bug 718939.

I see this on 10.7.3 as well using Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:13.0a1) Gecko/20120208 Firefox/13.0a1

Weird - at first I could reproduce this, but after restarting on 10.7 I noticed that I was able to invoke full screen.

Marcia, if you run into this again, can you open the Web Console and see if there's an error message listed there describing why the failure occurred? Thanks.

I'm also able to replicate this error using 10.7.3 on a MacBook5,1. Restarting my machine did not fix the issue, and there are no errors in the web console.

I ran into this again in the QA lab on a 10.7.2 machine. I checked the error console and there was nothing in it. Adding QA wanted to get some wider testing.

In testing again on the lab machine, I can reproduce this consistently with my existing trunk profile that has one extension. When I created a new profile on the same machine, I cannot reproduce it. Using Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:13.0a1) Gecko/20120209 Firefox/13.0a1. The only addon I have installed in the trunk profile is the MemChaser extension. The QA lab machine is 10.7.2 running on a Mac Mini. Virgil - Are you still able to reproduce this?

Is the machines on which this bug occurs dual-monitor? I'm aware of some issues with dual-monitor and fullscreen mode.

(In reply to Marcia Knous [:marcia] from comment #6) > Virgil - Are you still able to reproduce this? Can reproduce with Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:13.0a1) Gecko/20120209 Firefox/13.0a1 Though I'm having the same strange behaviour. Couldn't initially replicate with a clean profile, but after using other profiles and returning I've spotted this again. No messages in the Error Console for me either. Neither does this seem to be related to any extension. (In reply to Chris Pearce (:cpearce) (on paternity leave, don't expect quick response!) from comment #7) > Is the machines on which this bug occurs dual-monitor? None of the machines on which I could replicate use dual monitor.

Never used a dual monitor on this MBA and experiencing the same with OS X 10.6. No errors in the console, didn't try with a clean profile or safe-mode, yet.

None of the machines I tested on was using a dual monitor.

WFM on [Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:13.0a1) Gecko/20120213 Firefox/13.0a1] In addition this cannot be a regression following bug 718939 as reported in comment 0, since that bug only changed code on Windows, and this bug is being reported on Mac OSX 10.7. (In reply to Marcia Knous [:marcia] from comment #6) > In testing again on the lab machine, I can reproduce this consistently with > my existing trunk profile that has one extension. When I created a new > profile on the same machine, I cannot reproduce it. Marcia: if you enable the Memchaser extension in your new profile, does the bug reproduce? If you disable the extension in your main profile does the bug not reproduce?

(In reply to Chris Pearce (:cpearce) from comment #11) > WFM on [Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:13.0a1) > Gecko/20120213 Firefox/13.0a1] > > In addition this cannot be a regression following bug 718939 as reported in > comment 0, since that bug only changed code on Windows, and this bug is > being reported on Mac OSX 10.7. Managed to replicate consistently on the Mac Nightly TryServer builds from bug 718939 (two machines). And I couldn't reproduce on the previous Nightly, so I supposed that bug 718939 is the faulty one, but I'm prepared to pull back on that one now given the circumstances. Tried on 20120213 Firefox/13.0a1, the same two machines. Full screen mode worked fine now. Will still keep an eye on this, though.

It is very likely that this bug was caused by 1b0294c7b952, sorry about that. If this is the case it should have been fixed by 5f033ecdf2aa which landed two days later. Nightly 2012-02-10 is the first one to contain both changes which explains that you are are not seeing the problem with 2012-02-13. Note that this was also reported in bug 725456.

Since this doesn't seem to be reproducible anymore and the information from comment 13, I'm going to dupe this to bug 725456.