User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/37.0.2062.120 Safari/537.36 Steps to reproduce: 1. Click on any menu Actual results: The menu doesn't render immediately. It can take up to 30 seconds or more. If I click on the empty space where a menu option should be, the option works as expected. I just can't see what they are. Expected results: The menu should display.

This is a new install of Thunderbird 31.1.1 running the default profile on Windows 7 Pro. No extensions or Add-Ons are installed. Restarting Thunderbird in Safe Mode appears to fix the issue. The only thing I can find that is disabled by doing that is the default theme.

What theme are you using, Seth?

I am using the default theme that ships with Thunderbird. It is a completely clean install on a computer that hasn't had Thunderbird on it before.

(In reply to Seth Randall from comment #1) > The only thing I can find that is disabled by doing that is the default theme. Thanks for testing in safe mode. Many things are disabled other than addons and themes. One of them is mozilla's graphics hardware acceleration (HWA) hardware acceleration can be controlled by the preference gfx.direct2d.disabled in about:config - when its value is true, then HWA is disabled. access about:config at Toosl | options | advanced | general | config editor

Disabling HWA appears to have fixed the issue. Does that mean there's a bug in Thunderbird or the video driver (or possibly both?) Regardless, I don't really need HWA I'm guessing, so I will run with it off for now.

(In reply to Seth Randall from comment #5) > Disabling HWA appears to have fixed the issue. Does that mean there's a bug > in Thunderbird or the video driver (or possibly both?) > > Regardless, I don't really need HWA I'm guessing, so I will run with it off > for now. Thanks for the update. Can you post the graphics section information from Thunderbird's Help | Troublshooting. And also check to see if you have the latest video driver?

bug 950133 reenables HWA

(In reply to Wayne Mery (:wsmwk) from comment #7) > bug 950133 reenables HWA I've attached pictures of the Graphics section from Troubleshooting. I loaded the latest driver from NVidia (I believe I was using the default Lenovo one before) and the problem appears to be gone now.

I find that turning off layers.offmainthreadcomposition.enabled without disabling hardware acceleration completely also works.

(In reply to Philip Chee from comment #11) > I find that turning off layers.offmainthreadcomposition.enabled without > disabling hardware acceleration completely also works. CC: :mattwoodrow perhaps he can supply some insight on what's happening.

Switching ni to Bas, since this looks like a windows OMTC regression.

Another data point: (From bug 950133 comment #2) > JFTR, this change made Thunderbird scroll jerky again (in the mail list > pane, most notably in an unmaximized TB window) on my Win7 64bit system with > AMD Radeon HD 7700. > > Manually setting "gfx.direct2d.disabled" to "true" reverted TB to perfectly > smooth scrolling in the mail list pane (and everywhere else).

This is likely caused by some form of GPU contention, what I can't explain is why we don't have similar reports for firefox.

(In reply to Bas Schouten (:bas.schouten) from comment #15) > This is likely caused by some form of GPU contention, what I can't explain > is why we don't have similar reports for firefox. I can reproduce this on Mozilla/5.0 (Windows NT 6.1; WOW64; rv:35.0) Gecko/20100101 Firefox/35.0 So possibly a driver issue.

Seth, have you been able to resolve this with a driver update for your Nvidia 5400M?

(In reply to Wayne Mery (:wsmwk, use Needinfo for questions) from comment #17) > Seth, have you been able to resolve this with a driver update for your > Nvidia 5400M? Wayne, I am now running 38.0.1. I've been running with layers.offmainthreadcomposition.enabled set to false for a long time now. I'd forgotten I'd even done it. It's set to true now and things look just fine.

(In reply to Philip Chee from comment #16) > (In reply to Bas Schouten (:bas.schouten) from comment #15) > > This is likely caused by some form of GPU contention, what I can't explain > > is why we don't have similar reports for firefox. > > I can reproduce this on Mozilla/5.0 (Windows NT 6.1; WOW64; rv:35.0) > Gecko/20100101 Firefox/35.0 > > So possibly a driver issue. Philip, can you still reproduce?

> Philip, can you still reproduce? Nope. Looks like it's now WORKSFORME