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Firefox Major Memory Leak

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  • Last reply by cor-el

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Ever since today, firefox has been very slow with youtube, and I noticed it's been having a memory leak. Every time I load a video on there ram usage spikes by about 1 gb, then gradually increases over time (It never goes down). Also cpu usage when loading a page is really high (almost 100% usage). How do I fix this? I tried all the solutions google had to offer but nothing worked. Never had any problem like this for over the 10 years I've been using firefox

Ever since today, firefox has been very slow with youtube, and I noticed it's been having a memory leak. Every time I load a video on there ram usage spikes by about 1 gb, then gradually increases over time (It never goes down). Also cpu usage when loading a page is really high (almost 100% usage). How do I fix this? I tried all the solutions google had to offer but nothing worked. Never had any problem like this for over the 10 years I've been using firefox

Modified by CheeseIts

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Start Firefox in Troubleshoot 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 Troubleshoot Mode start window

You can check the about:memory and about:processes pages for info about all processes. See also the about:unloads page for info about the tabs.