Disable fullscreen entirely

[pintassilgo]

It's possible?

I know I can disable F11 with dorando keyconfig, but the problem is the doubleclick on HTML5 video that puts it in fullscreen.

Is there any way to disable fullscreen in Firefox?

[Grumpus]

There's a few items in about:config which might do the job but this would be something you would have to try.
Make sure you keep a record of what you change on paper so if something doesn't work you can change it back to what the original condition was.
Also, there's no telling how these changes would react with extensions so it might be good to create a second, clean profile to see what happens.
When you open about:config search for "full-screen", "fullscreen" (both are represented) and "screen". Probably one of the API related, best guess.
If you have Classic theme restorer installed this has some full screen controls but nothing listed hides but relates to a couple of the fullscreen items in about:config.
Good Luck

[therube]

(You can use REGEX-like syntax, so /full.*screen/, should find both "full-screen" & "fullscreen". The / & / demarcate the use of REGEX. More, about:config.)

kb.mozillazine.org/About:config#Search_bar