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Firefox 79 is extremely slow

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  • 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.

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.