Try your uninstall this way for Firefox. Uninstall then : Delete the Mozilla Firefox Folders in C:\Program Files and C:\Program Files(x86) Then restart system. Then run Windows Disk Cleanup. Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved.

Reinstall with Current Release Firefox 57.0 with a Full Version Installer https://www.mozilla.org/firefox/all/ Note : Legacy Extensions will be disabled and or removed.

If still issues there are some setting Tool --> Options --> Performance Untick all and change the recommended cores to lower.

Going back : unfortunately 56.0.2 is no longer safe to use for every day use, but 52.5.0 ESR is! It will continue to get security updates until May 2018, and you can download and install it from this page: https://www.mozilla.org/en-US/firefox/organizations/all/

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

Hi, thanks for a quick reply. When I uninstall it any Firefox folder in x86 disappears anyway so there isn't anything to delete?

Update: Just done another uninstall and then searched any Firefox files and deleted everything. Downloaded 57 and installed it then opened it again. It said it could see I was reinstalling and did I want to refresh so I did. Sadly this has made no difference. I've not got any add ons installed anymore and nothing other than pure new Firefox 57 and it's just soooooooo laggy and slow.

That's to bad as really wanted a clean install. Try these : 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). Is the problem still there?

https://support.mozilla.org/kb/Firefox+is+already+running+but+is+not+responding

https://support.mozilla.org/en-US/kb/firefox-slow-how-make-it-faster

https://support.mozilla.org/en-US/kb/firefox-uses-too-many-cpu-resources-how-fix

https://support.mozilla.org/en-US/kb/firefox-uses-too-much-memory-ram

https://support.mozilla.org/en-US/kb/firefox-hangs-or-not-responding

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

Hi, sadly it's still an issue when in safe mode.

Also THANK you so much for your help it's much appreciated regardless.

Old out dated Video Card Drivers are a major issue : Update if you can, if do not know what card/chip you have GPU-Z https://www.techpowerup.com/gpuz/ can provide that information so that you can google for them.

Would the graphics driver really make it run badly when everything was fine before? Also it is purely Firefox that's a mess? It seems to hog so much resources also?

I have checked the graphics driver and it's the most up to date one apparently?

I'm using Chrome to try and fix it and it's so nice using a browser that works quickly.

Yes Firefox new engine is CSS and reads pages as such and converts to pixels to display. But most errors and crashes and more come down to video card drivers for any version of Firefox.

I am getting to be at a loss if it will not reinstall cleanly. Option : should not do this but Firefox Based Alternatives https://www.palemoon.org/ https://www.waterfoxproject.org/ https://www.comodo.com/home/browsers-toolbars/icedragon-browser.php https://www.gnu.org/software/icecat/ www.cometbird.com/ I run this as a 2nd browser https://www.seamonkey-project.org/ is like Netscape with mail and HTML Editor. www.cometbird.com/ https://www.torproject.org/projects/torbrowser.html.en https://vivaldi.com/?lang=en

Other thing is to let this sit and see if someone with more knowledge can figure it out.

I just updated Firefox on my ancient PC and it works fine with a really really old graphics card. I will to a complete pc reset tomorrow and hope it works :(

Hey Guy's I have great news although it's not totally practical... I done a full new Windows install and it has fixed it (touch wood). So far seems to be working well.

Hopefully this helps others but as I said it's not really practical :(

Quote - as entered into Firefox - "New Firefox 57 is SLOWER THAN SLOW."

Example: In Firefox, I had to wait 15 seconds for the last 1/2 of the above statement to register and be displayed ("SLOWER THAN SLOW").

I have a newer Intel I7, 16GB RAM, 4 monitor, Windows 10 computer. This is not a computer issue.

I Followed web instructions to reload Firefox 56.2 - even turned off Firefox updates. FF56.2 worked as it should, without any lags.

The following morning (today), Firefox had upgraded itself back to FF57.

The reason that I could enter THIS TEXT is simple - Begrudgingly, I am forced to use Google Chrome for Internet access. Chrome works as Firefox should work - fast, reliable.

Bottom line: If Mozilla cannot fix their product, I will be forced to use competitors' browsers. Please don't let it come to that!!!!

Signed, Fiercely Firefox Until Today.

PS: Unless my computer has major issues, there is no chance of reinstalling Windows. Every other program works as they always have.

PPS: As suggested, I ran FF57 in Safe Mode. Nothing changed - just as slow as ever!

I have the same problem as above. Firefox is slow and laggy and unusable. Additionally the memory usage is off the charts! Compared to Chrome and Edge which I just switched to since Firefox is unusable. So disappointed that the last version was fast and snappy and this one is as slow as molasses in every respect. I've even done a reset and that did nothing. Will waiting for the next release solve the performance and memory issues? I have little time to experiment with different solutions. This has been a quantum leap backwards.

Same, unuseable with quantum. When installing old version of firefox it's necessary to set firefox options disabling automatic update. But since mozilla won't maintain security of old versions it may be necessary to move to another browser for those like me with this problem.

I had same problem until I found this solution: enter about:config into the firefox address bar (confirm the info message in case it shows up) & search for the preference named accessibility.force_disabled. double-click it, change its value to 1 and restart firefox once. I did this and now all is well.

Above is copied from another post. Scroll and text commands now all work fine. Hope this works for all of you.

Update: Just found the normal way into this setting

    Click the menu button Fx57Menu and choose Options.
   Select the Privacy and Security panel.
   Go to the "Permissions" section.
   Check the Prevent accessibility services from accessing your browser checkbox.
   Restart Firefox.

Thanks, Bob.E.K. That fixed my slow and laggy problem that version 57 caused. Now if I could get someone to explain to me how to fix my Firefox Health Report which stopped working many updates ago.

Thanks, Bob! Issue has been fixed! Thanks to forums such as this one, the community can help one another with their issues. Thank you very much! Ken.

Wow Bob E.K. It's a Thanksgiving miracle! So simple and that nailed it. Thanks so much. I just felt that the solution had to be simpler than some of the other ones presented in this thread. Hope this works for everyone else.

Thank you Bob E.K. I have been driven mad with this issue and had tried everything else, but this worked!!!! THANK YOU!!!

Thank you, thank you, Bob E.K.! To Mozilla: why would you set defaults that slow the application like this one did or make the user experience difficult like the switch to the unreadable black tabs? Some of us will find solutions and stick around, but many other users will just drop your product for another. It's almost like you're trying to get rid of us.

chris.uk said

Hi, I'm hoping so much you guys can help. I sadly got the update to Firefox 57 this morning and it's pretty much made it useless. I have an Intel i5-4258U CPU @ 8GB of RAM running Windows 10 and prior to this update I never had an issue with Firefox. Don't get me wrong the update looks nice and I'm sure it would be great but this version has pretty much broken being able to use it as it is just so slow and laggy the browser is unusable. When I type anything I have to wait for the browser to catch up which can take minutes. I can't browse a shop website because it's so slow. Scrolling is horrible as it scrolls a little then stops and scrolls a bit more then stops. I tried watching stuff on Youtube and the page plays the video sound but the image is still until it's caught up. I uninstalled the browser and reinstalled it but no change. I managed to find 56 on the site and installed that again after removing 57 and it worked but straight away it had downloaded the 57 update again and as soon as I opened it again the 57 had been installed again. I've not seen a way to completely stop any auto update? I don't put this down to my computer because it's more than capable of running Firefox and has never let me down. Chrome Opera and Edge all run fine still while Firefox grinds to a halt.

Install older version 52.5. fixes slow problem