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Slow download / upload speeds only in Firefox

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  • 1 has this problem
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  • Last reply by Ross

Ross
Ross
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If I check my internet speed in Firefox using various speed test websites, it shows 50Mb download, and upload shows about 9Mb. In any other Browser it reports 70Mb down and 20Mb up. It has been 70 up & 20 down for some years. If I restart Firefox in safe mode, I get 70Mb / 20Mb as expected. If I remove Add-ins, it is still slow. I tried a refresh, and it's still slow. I have no extensions, themes and have turned hardware acceleration off. Changing the proxy settings doesn't help either.

If I check my internet speed in Firefox using various speed test websites, it shows 50Mb download, and upload shows about 9Mb. In any other Browser it reports 70Mb down and 20Mb up. It has been 70 up & 20 down for some years. If I restart Firefox in safe mode, I get 70Mb / 20Mb as expected. If I remove Add-ins, it is still slow. I tried a refresh, and it's still slow. I have no extensions, themes and have turned hardware acceleration off. Changing the proxy settings doesn't help either.

Modified by Ross

All Replies (3)

ANAMIKA KUMARI
ANAMIKA KUMARI
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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. 

   https://support.mozilla.org/kb/Firefox+is+already+running+but+is+not+responding
   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
Ross
Ross Question owner
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I tried all the recommended changes, but I still get slow download / upload speeds. I think the changes suggested are for improving performance of Firefox (CPU usage, start-up etc), not for improving data download / upload speed?

Ross
Ross Question owner
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I installed Firefox 72 through 74.0.1 and all gave me the download & upload speeds I would expect. I installed Firefox 75 and the download & upload speeds dropped considerably. I cannot see anything in the release notes for Firefox 75 that would account for this? Whatever it is, has been carried forward through to Firefox 78.