Try to disable accessibility services in Firefox.

• 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

Current Firefox releases have multi-process windows enabled. You may see three or more Firefox processes running.

• one process for the main Firefox thread (user interface)
• one or more processes for content threads set via "Options/Preferences -> General -> Performance" (dom.ipc.processCount)
• one process for the compositor thread (Windows)

You can look in "Help -> Troubleshooting Information" (about:support) to see the current multi-process state.

• "Help -> Troubleshooting Information" -> "Application Basics":
  Multiprocess Windows
  Web Content Processes

See also:

• https://support.mozilla.org/en-US/kb/firefox-slow-how-make-it-faster
• https://support.mozilla.org/en-US/kb/firefox-uses-too-much-memory-ram

https://www.howtogeek.com/332449/whats-new-in-firefox-quantum/ https://www.howtogeek.com/334594/stop-complaining-that-your-browser-uses-lots-of-ram-its-a-good-thing/ Not called Quantum for nothing. do this please for ecissive ram/cpu use : 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.

Monitor in Task Manager. Should stay below 2 gigs. If excessive then do below and monitor and change if need to...Test and go up again , go back down, it will eventually get a zone you and it can live with.

Go to the 3 Bar Menu then Options --> General --> Performance and untick everything. change the recommended size lower then see how it runs. Note: 1 = No Multiprocessor = slow again. Try 2 Restart Firefox after making these changes please.

Also Extensions put them in, approx 20megs give or take per extension.

Turn on the Bookmark Toolbar : Mouse to top of Browser and Right Click and Click Bookmark Toolbar. If Bookmark Toolbar is empty Look in your Bookmarks and look for another Bookmarks tool bar Folder and drag them out of there and into the Folder or the bar.

fyi : Always do this : https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer to HTML (mine are from 95) https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

Anything else not covered ?

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