Update: Finally, Firefox 3.6 (and onwards hopefully!) support fullscreen. Just Press the Command key + Shift key + F, or go to View > Full screen. Nevertheless, the method below might still be useful if you want to make the Firefox window a particular size, say 1024*768 or something like that for testing purposes._______________________
Mac: Hi, I'm a Mac. I look cool and interesting.
PC: And I'm a PC. I look ugly and boring.
Mac: Dude. You're so boring.
PC: I sure am.
Mac: I rock.
PC: Ya sure do.
- Some Apple commercial where Apple makes fun of "personal computers".
Yup. The Apple commercials sure are right. There is huge different between the Mac and PC lifestyles. I've been a
switcher recently. And one big problem that I ran into recently is that a lot of things on the PC side aren't quite available to the Mac users.
Usually, when I'm on the PC, I hit F11 and Firefox goes into full screen mode. However, when I'm on Tiger or Leopard for that matter, hitting F11 will only show you your desktop. You can change that however through system preferences, but there's no way of going fullscreen on a mac :(. For other cocoa applications, Ian Henderson created a really lightweight and useful app/plug-in called
megazoomer, but Firefox isn't exactly a cocoa application.
So, after searching the inter web for a while, I came across this
lifehacker post. I then searched a bit more to find out what you can do with javascript and a bookmarklet. Turns out, you can do a lot.
To be honest, it's not possible to maximize a firefox window completely on a mac. However, it is possible to maximize the window to fit in the whole screen. To do this just follow these steps:
1. Create a new bookmark by right clicking on the bookmark toolbar. If you don't see the bookmark toolbar just go to View > Toolbars > check Bookmark toolbar.
2. Give the bookmark a name like Fullscreen (something that you can remember) and then paste the code below in the Location box. Make sure you paste all the code in 1 line only though, or else it won't work.
javascript:self.moveTo(0,0); self.resizeTo(screen.availWidth,screen.availHeight);

3. Click OK, and then just click on the Fullscreen button to maximize Firefox.
Then once you click on the Fullscreen Button, Firefox should then take up all the space that OS X allows an application to take up, depending on the size and position of your dock. Sometimes, when I'm viewing pictures, I like to minimize the dock by pressing Cmd + Option + D and this will allow Firefox to take up more space.
Do let me know if you find other ways of going Fullscreen in Firefox or any other Mac app for that matter.