You can see when your Firefox updated by checking the Troubleshooting Information page. Either:

• "3-bar" menu button > "?" button > Troubleshooting Information
• (menu bar) Help > Troubleshooting Information
• type or paste about:support in the address bar and press Enter

In the first table on the page, on the Update History row, click the "Show Update History" button. You probably have 57.0.4 by now?

Recent updates have been very minor fixes, so that's probably not the cause of any change.

Try to disable accessibility services in Firefox if it is currently enabled.

• Options/Preferences -> Privacy & Security -> Prevent accessibility services from accessing your browser
• https://support.mozilla.org/en-US/kb/accessibility-services
• http://techdows.com/2017/08/firefox-57-prevent-accessibility-services-accessing-browser.html

See also the Accessibility section on the "Help -> Troubleshooting Information" (about:support) page.

jscher and cor-el, I am running 57.0.4. I am always aware when there is an update. I will check out the Accessibility section.

It's just that Firefox was SO bad and now it seems to be running as it used to.

I did check or tried to check the Accessibility section but never could find it. I thought I followed your instructions as stated here? I was so hoping you folks would say you had noticed a difference. I sure have. Guess I should just be happy,

Thanks so much.

Yes there is a difference as it is using 4 cores of your CPU Chip if have 4 or more and not 1 as previous 53 or so did. Also all is tuned on for Multiprocessor now in 57. Ver 58 will bring Multi-Thread Processing. https://www.howtogeek.com/332449/whats-new-in-firefox-quantum/

go to the Firefox 3 Bar Menu --> Options --> Privacy & Security panel and under Permissions check (put a tick in the box) the setting to Prevent Accessibility Services from accessing your browser.

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

Pkshadow, I finally found the Permissions Tab and put a check mark in the box. I hope I did the right thing.

Guess I'll find out soon enough.

Thanks.

After I checked that box, my FF starting running slow again. So I went in and unchecked it all seems better?

Have NO idea what the deal was, but will leave it unchecked for a while.

Thanks.

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