User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:5.0) Gecko/20100101 Firefox/5.0 Build ID: 20110615151330 Steps to reproduce: Set up a dual-monitor configuration, one screen above the other one (secondary on top, primary on bottom). Launch Firefox on the secondary screen in maximized mode. Actual results: There is a white line (1px height) on the bottom of the screen that is not taken by the application window, i.e. Firefox maximizes incorrectly. Expected results: That empty line should also be taken by Firefox window.

Can you reproduce this with the default theme (ie, in Safe Mode)?

Yes, it is reproducable with the default theme. It's just a bit less noticeable, but annoying while on a dark web-site. Do you need my hardware details?

Please post the graphics section from about:support

Videocard description NVIDIA GeForce 8400M GS Vendor code 10de Device code 0427 Video memory size 256 Video drivers nvd3dumx,nvwgf2umx,nvwgf2umx nvd3dum,nvwgf2um,nvwgf2um Driver version 8.17.12.7533 Driver date 5-20-2011 Direct2D enabled true DirectWrite enabled true (6.1.7601.17563, font cache n/a) Visualizer WebGLGoogle Inc. -- ANGLE -- OpenGL ES 2.0 (ANGLE 0.0.0.611) Hardware accelerated windows 1/1 Direct3D 10 I had to translate the strings, because they were in English.

> I had to translate the strings, because they were in English. In Russian, sorry. And, by the way, that stripe started blinking frequently recently.

Videocard description NVIDIA GeForce 8400M GS Vendor code 10de Device code 0427 Video memory size 256 Videocard drivers nvd3dumx,nvwgf2umx,nvwgf2umx nvd3dum,nvwgf2um,nvwgf2um Driver version 8.17.12.8026 Driver date 8-3-2011 Direct2D enabled true DirectWrite enabled true (6.1.7601.17563) ClearType settings ClearType settings not found Visualizer WebGLGoogle Inc. -- ANGLE -- OpenGL ES 2.0 (ANGLE 0.0.0.686) H/W accelerated windows 1/1 Direct3D 10 Problem persists in versions 7beta1 and 8a2

We also have this problem at work. Because we use a full screen web browser to display slideshows for digital signs we can not use Firefox as the web browser for our digital sign networks.

(In reply to Jason Ross from comment #7) > We also have this problem at work. Because we use a full screen web browser > to display slideshows for digital signs we can not use Firefox as the web > browser for our digital sign networks. Forgot to say that this problem is present on both Linux and Windows versions of FireFox.

I can confirm that, some line at the bottom on secondary screen. On single screen when in full screen there is a one pixel (rgb-0,0,0) line at top. To see this just do a screenshot with white page at fullscreen. Another way to see this is go to http://ie.microsoft.com/testdrive/Performance/FishIETank/Default.html and hit F11 to full screen, at the right you will se that the screen size will be 1px less at top ex:1280x799px. Similar thread at the forum: http://forums.mozillazine.org/viewtopic.php?p=10082711#p10082711 (1280x1023) (1920x1199)

I can also confirm this. It doesn't seem to matter if you have a dual monitor setup, at least for me. I suggest we update the summary. This problem also occurs in DOM full-screen mode (mozRequestFullscreen). I assume it's the same bug. If not, I can file a separate one. (Side note: In the IE Fish Tank one can see that the correct height is reached, during the transition to regular fullscreen mode, but then decreased by one px)

(In reply to Daniel from comment #10) > This problem also occurs in DOM full-screen mode (mozRequestFullscreen). I > assume it's the same bug. If not, I can file a separate one. Actually, this only happens if I have sometime in the browsing session entered the regular fullscreen mode. STR: 1. Restart browser 2. Go to https://developer.mozilla.org/samples/domref/fullscreen.html 3. Hit enter to go fullscreen 4. Execute "document.getElementById('myvideo').clientHeight;" in the console in windowed mode (open with ctrl+shift+k and choose "Position > Window") 5. Observe correct height 6. Hit esc and then f11 twice to jump in and out of regular fullscreen mode 7. Repeat step 3 and 4 8. Observe incorrect height (-1 px)

This bug is still present in fullscreen mode. Height is 1 pixel less, than it should be... To verify go to http://whatsmy.browsersize.com/ press F11 and refresh the page with F5. Please mark the bug at least as confirmed.