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How to disable fullscreen permission and window.onbeforeunload popup permamently?

  • 2 replies
  • 17 have this problem
  • 15059 views
  • Last reply by 4Corvus

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I never want to see the fullscreen permission dialog or the "are you sure you want to leave this page" dialog popups. They are only annoying.

Chosen solution

You can set the dom.disable_beforeunload pref to true on the about:config page to disable this alert.

  • dom.disable_beforeunload = true

The only choices for full screen permissions are "Always Ask" and "Block". You can manage the full screen permission via "Tools > Page Info > Permissions" or via the about:permissions page.

You can toggle this pref that is aimed at developers to false if you want to suppress this dialog.

  • full-screen-api.approval-required = false

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.

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All Replies (2)

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Chosen Solution

You can set the dom.disable_beforeunload pref to true on the about:config page to disable this alert.

  • dom.disable_beforeunload = true

The only choices for full screen permissions are "Always Ask" and "Block". You can manage the full screen permission via "Tools > Page Info > Permissions" or via the about:permissions page.

You can toggle this pref that is aimed at developers to false if you want to suppress this dialog.

  • full-screen-api.approval-required = false

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.

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cor-el said

You can set the dom.disable_beforeunload pref to true on the about:config page to disable this alert.
  • dom.disable_beforeunload = true

The only choices for full screen permissions are "Always Ask" and "Block". You can manage the full screen permission via "Tools > Page Info > Permissions" or via the about:permissions page.

You can toggle this pref that is aimed at developers to false if you want to suppress this dialog.

  • full-screen-api.approval-required = false

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.

THANK. YOU. SO. MUCH.