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F11 is grayed out. How can I restore it's funtion?

  • 4 replies
  • 1 has this problem
  • 3 views
  • Last reply by cor-el

rsbrux
rsbrux
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Until recently I could invoke (or exit) full screen mode with the F11 key. Now both F11 and F12 (for Firebug) are greyed out in the View menu and no longer work. I have not installed any new add-ons recently, so I presume that the cause is a recent update to either Firefox or to my OS. I am using Firefox 50.0.2 under Windows 8.1 Professional x64.

Until recently I could invoke (or exit) full screen mode with the F11 key. Now both F11 and F12 (for Firebug) are greyed out in the View menu and no longer work. I have not installed any new add-ons recently, so I presume that the cause is a recent update to either Firefox or to my OS. I am using Firefox 50.0.2 under Windows 8.1 Professional x64.

Chosen solution

Actually, the problem has gone away by itself! F11 still appears in gray in the View menu, but now it works again. I had Adobe Flash running in one of my tabs when it was disabled. Could that have blocked F11 somehow?

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All Replies (4)

FredMcD
FredMcD
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Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac=Options) key, and then starting Firefox. A small dialog should appear. Click Start In Safe Mode (not Refresh).

Is the problem still there?

rsbrux
rsbrux Question owner
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Chosen Solution

Actually, the problem has gone away by itself! F11 still appears in gray in the View menu, but now it works again. I had Adobe Flash running in one of my tabs when it was disabled. Could that have blocked F11 somehow?

FredMcD
FredMcD
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I don't know. Let's hope it stays gone. Safe Surfing.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Note that you can use one of these to leave Full Screen mode:

  • press the F11 key
  • click the Maximize button at the right end of the Tab bar
  • click the Full Screen button in the "3-bar" Firefox menu button drop-down list
  • right-click empty space on a toolbar and click "Exit Full Screen Mode"