Where is this "maximize"? Is it an add-on? A button I'm not seeing?

edit: why the downvotes? I'm at work on my rickety WinXP corporate box, and FF4 definitely does not behave as described above. (Do really think I didn't try that?!)

F11

Maximize as in what your OS allows you to do.

edit: Oh, Windows XP. You'll have to disable the menu bar to get it to work there, I think.

check. That works, thanks!

this should be shipped on be default.

edit: "this" appears to be as yet undefined. Unless ... can someone point me to whatever "maximize" is?

edit: FF4 does not behave as you describe on my WinXP box at work.

Press the little button in the titlebar that makes any window fill the screen.

Note that tabs will appear in the titlebar when maximized on Windows only, for Firefox 4, and only if you have the menu bar hidden. (It's hidden by default in Windows Vista and 7.) Tabs in the titlebar are planned for Mac and Linux too, but weren't ready for this release.

For whatever reason, the voters seem to think I didn't try that before commenting. FF4 does not behave as described on my WinXP box at work.

Hm, don't know what to say. Perhaps disable the menu bar. That did it for me.

Here's what firefox 4 looks like running on windows XP: http://img855.imageshack.us/img855/460/20110322144851800x600...

they probably don't have xp anymore. works fine on 7.