You can use full screen mode by pressing F11 on your keyboard. In full screen mode all toolbare are hide and you have the website in a full screen mode.

When I press F11, the browser goes fullscreen, but no toolbar is hidden.

That's why I asked this question.

I can try with a blank profile, if you think Firefox (on OS X) should do what you say.

You can right-click the toolbar when in full screen mode and set the check-mark on Hide Toolbars (about:config - pref: browser.fullscreen.autohide)

I just tried with a blank profile and I confirm that it's not caused by any of my extensions or settings.

cor-el, my context menu on the toolbar, while in full screen, does not have that option. I only see Navigation Toolbar, Bookmarks Toolbar, Add-On Bar, (separator), Tabs on Top, Customize

1. In the Location bar, type about:config and press Enter. The about:config "This might void your warranty!" warning page may appear.
2. Click I'll be careful, I promise!, to continue to the about:config page.

Searche the string "browser.fullscreen.autohide"

That's weird. My setting browser.fullscreen.autohide was already set to true, but it doesn't work. Changing it seems to do nothing. I've entered and exited fullscreen, restarted Firefox… nada.

You can check for problems caused by a corrupted localstore.rdf file.

• http://kb.mozillazine.org/Corrupt_localstore.rdf

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Firefox/Tools > Add-ons > Appearance).

• Do NOT click the Reset button on the Safe Mode start window.

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

I just tried Safe Mode. Still nothing. The default setting is true, but it doesn't work. I tried changing it back and forth, and going back and forth into fullscreen, but nothing. The toolbars are always shown.

Could it be because I'm on Mac OS X 10.7 Lion, that has its own fullscreen support? (Which Firefox is using since version 14)

If anybody else with OS X Lion or newer can confirm this behaviour, we might have to file it as a bug.

On Mac you would have to use Command+Shift+F to toggle full screen mode.

• https://support.mozilla.org/kb/how-to-use-full-screen

I just tried Command+Shift+F and it triggers the same Full screen mode as the View menu, with this very bug.

You can try to remove the Firefox plist file (org.mozilla.firefox.plist).

• http://www.macfixit.com/article.php?story=20060606082246983 How .plist files become corrupt and troubleshooting the results

Go to "~/Library/Preferences" and remove the plist file for Firefox (org.mozilla.firefox.plist)

Nope.

Thanks for all your suggestions though :-)

I'm having same issue, FF 24.0 and OSX 10.8.5. I go into FS mode via menu option or Shift+Cmd+F and still the tabs, address bar, and bookmark bar remain. Behavior identical in Safe mode. Ensured that browser.fullscreen.autohide = true. No way to hide them.

Defeats purpose of FS mode when I want to block out distractions. Haven't been able to use any of the add-ons to fix this either. Did something break in a recent build?

I tried all previous releases of Firefox (actually I did a binary search) and I found out this bug appeared between:

• Firefox 14.0.1 (en-US, Mac) in which the toolbar would auto-hide on fullscreen; and
• Firefox 15.0b1 (en-US, Mac) released a few days later, in which the auto-hide did not work anymore.

Both releases had browser.fullscreen.autohide=true as a default setting. I removed the entire Firefox folder in Application Support before launching each release.

This was all tested on the latest OS X 10.9 Mavericks. At my workplace I have access to Macs running most if not all previous OS X releases, so I can perform some tests on them if needed.

Can anybody please page a developer or open a bug report with this information?

There is a bug for this: 740148 – [10.7] Allow hiding toolbars for presentations. Looks like not much activity...

If you hadn't noticed this behavior until recently, perhaps you were using the Old Lion Fullscreen extension as a workaround?

Note on the bug tracking system: If forum members can contribute to the development, please feel free to pitch in. Otherwise, it's generally not helpful to add comments to bugs, but you can register on the Bugzilla site and "vote" for them to be fixed. See:

• Bugzilla Etiquette
• Voting

By the way, it might be possible to use a custom style rule to remove the toolbars in "Lion fullscreen" mode.

I do not have a Mac to experiment with, but on Windows, when you go into full screen, the individual toolbars and the toolbar area (#navigator-toolbox) get the attribute inFullscreen=true. It might be possible to target this area for removal based on that attribute if it's also present on Mac (i.e., so it's only removed when in full screen).

Using the suggestion from @jscher2000, I was able to get a fairly complete Stylish modification working.

This hides specific toolbars (in my case, the Personal Toolbar, the Web Developer Toolbar and Googlebar Lite), but re-shows them if you mouse over the toolbar area. It also removes the ~11px of padding at the top that exists for no reason that I can see.

It's easy to add other toolbars, but you need to use the DOM Inspector to inspect the chrome and find their IDs.

@namespace url(http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul);

#main-window[inFullscreen=true] {
    padding-top: 0px !important;
}

#navigator-toolbox[inFullscreen=true]:not(:hover) #PersonalToolbar,
#navigator-toolbox[inFullscreen=true]:not(:hover) #GBL-Toolbar,
#navigator-toolbox[inFullscreen=true]:not(:hover) #web-developer-toolbar,
#navigator-toolbox[inFullscreen=true]:not(:hover) .web-developer-toolbar {
    visibility: collapse;
}

Note: I'm not hiding the tab bar, because I use TreeStyle Tabs, and they autohide already. I believe this was #TabsToolbar or #TabToolbar