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Firefox slows down Windows 10 - window maximization lag

gulliwog
gulliwog
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When Firefox is running on my PC it will cause other programs to take a much longer time to maximize from the taskbar, there is up to a full second delay between clicking on the icon and the window appearing on the screen. This seems to affect any and all other programs which may be running at the same time as Firefox.

It's not a resource issue as I have an i9 with 32Gb 3200Mhz ram and I don't have much background stuff running at all. As soon as I close Firefox the problem stops. I don't know if it could be the pages I visit, although I visit the same ones with chrome and this doesn't happen.

When Firefox is running on my PC it will cause other programs to take a much longer time to maximize from the taskbar, there is up to a full second delay between clicking on the icon and the window appearing on the screen. This seems to affect any and all other programs which may be running at the same time as Firefox. It's not a resource issue as I have an i9 with 32Gb 3200Mhz ram and I don't have much background stuff running at all. As soon as I close Firefox the problem stops. I don't know if it could be the pages I visit, although I visit the same ones with chrome and this doesn't happen.

All Replies (1)

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 25 Contributor
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I'm concerned that there could be a CPU hogging coin miner or other unwanted code running in your Firefox, either in a page you opened or in one of your add-ons.

Could you test in Firefox's Safe Mode? In its Safe Mode, Firefox temporarily deactivates extensions, hardware acceleration, any userChrome.css/userContent.css files, and some other advanced features to help you assess whether these are causing the problem.

If Firefox is not running: Hold down the Shift key when starting Firefox. (On Mac, hold down the option/alt key instead of the Shift key.)

If Firefox is running: You can restart Firefox in Safe Mode using either:

  • "3-bar" menu button > "?" Help button > Restart with Add-ons Disabled
  • (menu bar) Help menu > Restart with Add-ons Disabled

and OK the restart.

Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

Any improvement?