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Firefox is being extremely laggy, how do I fix it?

  • 3 replies
  • 1 has this problem
  • 52 views
  • Last reply by Dub7

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Firefox is being very laggy, as is Chrome. The only browser I have that is working fine is Internet Explorer, but I do not wish to continue the use of I.E as it's naturally slow, no real lag, just slow. Firefox has been my go-to browser for years, and I'd really prefer not to have to stop using it now. Here are the details, over the last week Firefox has just been really terrible to use. It started with videos (YouTube etc) not playing correctly - the audio's fine, the buffering's fine, but the picture is very choppy. Chrome's doing this too but I.E is not, and nor are the videos I already have on my computer. Now Firefox is very slow to load other things as well, like Facebook, Twitter etc.

I've done a bunch of things to try and fix this - I tried refreshing firefox, uninstalling/re-installing, updating my graphics driver, enabling AND disabling preventing accessibility services, I tried optimizing and defragmenting my computer earlier but NOTHING seems to work. It's so frustrating. I just want to be able to use Firefox again without any issues.


Thank you.

Firefox is being very laggy, as is Chrome. The only browser I have that is working fine is Internet Explorer, but I do not wish to continue the use of I.E as it's naturally slow, no real lag, just slow. Firefox has been my go-to browser for years, and I'd really prefer not to have to stop using it now. Here are the details, over the last week Firefox has just been really terrible to use. It started with videos (YouTube etc) not playing correctly - the audio's fine, the buffering's fine, but the picture is very choppy. Chrome's doing this too but I.E is not, and nor are the videos I already have on my computer. Now Firefox is very slow to load other things as well, like Facebook, Twitter etc. I've done a bunch of things to try and fix this - I tried refreshing firefox, uninstalling/re-installing, updating my graphics driver, enabling AND disabling preventing accessibility services, I tried optimizing and defragmenting my computer earlier but NOTHING seems to work. It's so frustrating. I just want to be able to use Firefox again without any issues. Thank you.

Chosen solution

Hi, Preventing Accessibility Services Should be blocked and have a Check Mark in the box.

Please give your self a scan to eliminate that as a issue : https://www.malwarebytes.com/

Multi-Processor Support : Go to the 3 Bar Menu then Options --> General --> Performance and uncheck everything. change the recommended size higher then see how it runs. Note: 1 = No Multiprocessor = slow again. Restart Firefox after making these changes please. Monitor Ram and CPU usage in MS Task Manager.

Please run this MS DOS command to fix registry and system files, do the following: 1)Use the Windows key + X keyboard shortcut to open the Power User menu and select Command Prompt (Admin). 2)Copy/Paste the following command and press Enter: 3)DISM /Online /Cleanup-Image /RestoreHealth Reboot after.

If things are still slow and weird : please uninstall and follow this, also download the file from the location provided : important : uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

Reinstall with Current Release Firefox 61.0.1 with a Full Version Installer

Please let us know if this solved your issue or if need further assistance.

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Okay, update. I know I only posted this like a minute ago, but most web pages are acting normally now. However, the videos are still an issue, and now writing in text is laggy? For example, as I write this, the letters are appearing later than what I am typing them.

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Chosen Solution

Hi, Preventing Accessibility Services Should be blocked and have a Check Mark in the box.

Please give your self a scan to eliminate that as a issue : https://www.malwarebytes.com/

Multi-Processor Support : Go to the 3 Bar Menu then Options --> General --> Performance and uncheck everything. change the recommended size higher then see how it runs. Note: 1 = No Multiprocessor = slow again. Restart Firefox after making these changes please. Monitor Ram and CPU usage in MS Task Manager.

Please run this MS DOS command to fix registry and system files, do the following: 1)Use the Windows key + X keyboard shortcut to open the Power User menu and select Command Prompt (Admin). 2)Copy/Paste the following command and press Enter: 3)DISM /Online /Cleanup-Image /RestoreHealth Reboot after.

If things are still slow and weird : please uninstall and follow this, also download the file from the location provided : important : uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

Reinstall with Current Release Firefox 61.0.1 with a Full Version Installer

Please let us know if this solved your issue or if need further assistance.

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The scan seems to have worked! Cheers mate!