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 is causing the problem.

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

• https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode
• https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

You can create a new profile to test if your current profile is causing the problem.

See "Creating a profile":

• https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles
• http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Profile_issues

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.

• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

OK Just finished I started in safe mode, didn't help Made a new profile and didn't transfer any files from the old profile. New profile made no difference. I have switched back to default profile Cleaned all history and cache, didn't help

I have just noticed the time it says I posted the last reply as 5:17pm but my computer says it is 2:21pm which is correct.

ilikefree09 said

I have just noticed the time it says I posted the last reply as 5:17pm but my computer says it is 2:21pm which is correct.

OK I found how to fix the time problem, now just need the speed to improve or switch browsers again.

Boot the computer in Windows Safe mode with network support to see if that has effect in case security software is causing problems.

• http://www.bleepingcomputer.com/tutorials/how-to-start-windows-in-safe-mode/
• http://www.7tutorials.com/4-ways-boot-safe-mode-windows-10

I have managed to speed it up by going to black viper and setting my services to his tweaked settings. Don't really know the service that helped but can report it is now faster. Could now be marked as solved EDIT: Not solved slow again today, slower than an old version of Internet Explorer I keep just to download new browsers with.

OK I tried in safe mode with networking and it made no change. Tried again normally and switched off MalwareBytes Anti-Exploit and it made some slight difference so it may be a security thing. I don't run real-time anti-virus only anti-exploit and a key scrambler with ghostery and adblock plus add-ons enabled

Still slow, switching to chrome now

Glad to hear that your problem has been resolved. If you haven't already, *Please select the answer that solves the problem*YOURS. This will help other users with similar problems find the solution more easily. Thank you for contacting Mozilla Support.

Pkshadow said

Glad to hear that your problem has been resolved. If you haven't already, *Please select the answer that solves the problem*YOURS. This will help other users with similar problems find the solution more easily. Thank you for contacting Mozilla Support.

My problem is/was not solved. I tried a refresh and installed new add-ons and tested at each stage and the problem was with me all the way. Firefox is not working as it did a few months ago and I am going to restore my computer from an image file taken from before the problem started and turn off updating for Firefox and add-ons

now back on 52.4 and speed back