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Unknown website keeps stopping Firefox and locking up my computer

  • 2 replies
  • 1 has this problem
  • 6 views
  • Last reply by cor-el

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When I am scrolling through a website, reading articles, etc., I get a message in yellow at the top of the page with the image of a robot telling me that a website has interrupted Firefox with an option to wait, or stop it. This happens frequently, especially if I am scrolling through news pages etc., deleting History and Cookies on my computer doesn't seem to help.

When I am scrolling through a website, reading articles, etc., I get a message in yellow at the top of the page with the image of a robot telling me that a website has interrupted Firefox with an option to wait, or stop it. This happens frequently, especially if I am scrolling through news pages etc., deleting History and Cookies on my computer doesn't seem to help.

All Replies (2)

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What is/are the exact error message(s) ?


Many site issues can be caused by corrupt cookies or cache.

Warning ! ! This will log you out of sites you're logged in to. You may also lose any settings for that website.

If there is still a problem, 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). Did this help?

While you are in safe mode;

Try disabling graphics hardware acceleration in Firefox. Since this feature was added to Firefox it has gradually improved but there are still a few glitches.

How to disable Hardware Acceleration {web link}

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See:


Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration or userChrome.css is causing the problem.

  • switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes
  • do NOT click the "Refresh Firefox" button on the Safe Mode start window