We've seen a few reports of Firefox 18 "slanting" on Mac 10.6. We aren't sure what's going on here, and haven't been able to narrow down the cause (HWA, etc.) but we are getting this bug on file for tracking.

Another user with an about:support dump https://support.mozilla.org/en-US/questions/946607

I've been trying to reproduce this problem, but so far no luck. We don't have a machine whose resemble those in the report, especially the bit regarding the graphics card.

Can't reproduce this on MacBook Pro with 10.6.8 and a nVidia GeForce 9400M, new profile.

(In reply to Nick Thomas [:nthomas] from comment #4) > Can't reproduce this on MacBook Pro with 10.6.8 and a nVidia GeForce 9400M, > new profile. Thanks Nick! Makes me wonder if we should be asking our users to upgrade to the latest available 10.6 version.

Milan - can you help find an assignee to take a look at this today or early Monday? This is currently the #1 reported FF18 support issue.

Tyler, I don't see the about:support dump, but I really really want to see it in this case. I'm willing to bet these are 10.6.0, 10.6.1, 10.6.2 users - Apple fixed a *lot* of OpenGL things in 10.6.3, and we always force-disabled hardware acceleration on 10.6.x where x < 3, but I think we removed that force-disabling.

Yes, that code was removed for 32-bit builds of Firefox in bug 598401, which landed in Mozilla18. I'm going to go ahead and blame it.

This should fix the bug, if my diagnosis is correct.

This is a try build based on something approximating trunk: https://tbpl.mozilla.org/?tree=Try&rev=b146084841d4 and this is one based on Firefox 18, so support can try it out on affected users: https://tbpl.mozilla.org/?tree=Try&rev=70969d7d8523

If my diagnosis is correct, safe mode will also fix this, since safe mode disables hardware acceleration.

Support: Try getting people to try a build from http://ftp.mozilla.org/pub/mozilla.org/firefox/try-builds/jdrew@mozilla.com-70969d7d8523/try-macosx64/ and see if it makes a difference.

I pushed this to mozilla-inbound on the theory that it's unlikely to cause additional issues. If we can get someone to verify that it fixes the bug, I'll ask for approval to uplift. https://hg.mozilla.org/integration/mozilla-inbound/rev/ca9a07b19e79

Comment on attachment 701400 [details] [diff] [review] restore 10.6.2 check If low risk, I'd actually rather we got this on Aurora/Beta already to make sure it doesn't cause any new regressions, especially in the area of stability.

https://hg.mozilla.org/releases/mozilla-beta/rev/315a22f0d185 https://hg.mozilla.org/releases/mozilla-aurora/rev/dff581b63ec5

Comment on attachment 701400 [details] [diff] [review] restore 10.6.2 check [Approval Request Comment] Regression caused by (bug #): bug 598401 User impact if declined: Broken rendering on 10.6.2 and below. Testing completed (on m-c, etc.): m-c, aurora, beta Risk to taking this patch (and alternatives if risky): Not risky. Biggest problem is if it doesn't work.

QA wasn't able to reproduce this before but flagging for verification in 19 just in case we get lucky.

Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:19.0) Gecko/20100101 Firefox/19.0 Build ID: 20130215130331 I can't reproduce the initial "slant" on Mac OS X 10.6.8 (I don't have an older version of Mac OS X 10.6) and Firefox 18. Could anyone who was able to reproduce this issue (or has an older version of Mac OS X 10.6- like 10.6.1, 10.6.2 ) verify that is no longer reproducible on Firefox 19 RC?

Tagging [qa-] since we cannot reproduce this on allegedly broken builds. Tyler, can you watch for feedback to see if this is trending down now that we've fixed this?

We haven't seen this since 18 was released (I wasn't aware this was still open, sorry), it appears that all users that were affected either updated to 10.6.8, or to 18 (or both)