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Firefox 79 is extremely slow

  • 1 reply
  • 1 has this problem
  • 7 views
  • Last reply by FredMcD

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Since upgrading to Firefox 79 many Web pages are noticeably, irritatingly slower: Slow to load, and especially for interactive pages (Javascript, etc), slow to respond. Some are teeth-grindingly, give-up-on-Firefox slow.

I've downgraded twice to Firefox 77 and the slowness went away, but that isn't a choice anymore on my work computer.

Please get rid of whatever "improvements" have ruined version 79 and restore the performance of my preferred browser.

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Start Firefox in Safe Mode {web link}

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?


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

https://support.mozilla.org/en-US/kb/firefox-takes-long-time-start-up

https://support.mozilla.org/en-US/kb/quick-fixes-if-your-firefox-slows-down


MemTest LAST UPDATED : 27/09/2013 Could you please run a tool from http://memtest.org/ in order to check the integrity of your RAM?

You will need a thumb or disk drive to install it on.


Do you let Windows handle the page file or did you set a fixed size ? If you use a fixed size for the page file then try the former and let Windows handle the page file.