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How can I disable the built-in Firefox nag screen that websites can abuse to annoy me?

  • 2 प्रत्युत्तर
  • 7
  • 4 views
  • के द्वारा अंतिम प्रतियुतर DeathAndPain

DeathAndPain
DeathAndPain
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Hello everyone,

When I leave some web pages, a window pops up that says: "This site asks you to confirm that you want to leave. Any data you have entered may not be saved." (not literally; I translated the message from the German Firefox version but assume that it also exists in the English original)

This modal message window is identical no matter which web site opens it, so apparently it is not part of the actual web site, but part of Firefox itself (besides the fact that web sides cannot open modal Windows due to regular popups being blocked). It seems that web sites can set some sort of flag to indicate that this question should be posed in case the user simply closes the page, and Firefox heeds it.

Trouble is, most pages that use it are some sorts of advertisements, and either way, I know what I am doing. If I close a tab or the whole browser, then I mean it, so to me, this is but an annoying nag screen. How can I make Firefox stop displaying this for good?

Hello everyone, When I leave some web pages, a window pops up that says: ''"This site asks you to confirm that you want to leave. Any data you have entered may not be saved."'' (not literally; I translated the message from the German Firefox version but assume that it also exists in the English original) This modal message window is identical no matter which web site opens it, so apparently it is not part of the actual web site, but part of Firefox itself (besides the fact that web sides cannot open modal Windows due to regular popups being blocked). It seems that web sites can set some sort of flag to indicate that this question should be posed in case the user simply closes the page, and Firefox heeds it. Trouble is, most pages that use it are some sorts of advertisements, and either way, I know what I am doing. If I close a tab or the whole browser, then I mean it, so to me, this is but an annoying nag screen. How can I make Firefox stop displaying this for good?

All Replies (2)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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That is done via an onbeforeunload or onunload event that displays a JavaScript alert.

You can try to search for a Greasemonkey script to reset and block such events.

DeathAndPain
DeathAndPain प्रश्नकर्ता
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Unfortunately I know nothing about Greasemonkey or how to use it. Is there any solution that does not require being an expert? I would even call this a vulnerability if Firefox can this easily be triggered to display abuse windows.