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Speedtest.net and other speedtest sites behaving weird in Firefox only.

  • 1 reply
  • 1 has this problem
  • 9 views
  • Last reply by jonzn4SUSE

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I was trying to do a speedtest in FireFox and on speedtest.net, the font is wrong, when I do the download it stutters and lags before it gets to the final result. For example I have 350-400 down usually. speedtest.net for the download test will skyrocket and stutter to 330+, then stutter and skyrocket down to 120+ then to 200+ and then it will just end.

Other speedtest sites such as Speakeasy.net and Fast.com are hit or miss if they will show an upload speed. Sometimes they show the upload 0, sometimes it works like it seems its supposed to.

In Chrome and on my phone the tests all work just fine. Firefox seems to be having issues and I was curious if anyone else is experiencing these things or could shed some light. I have had problems with Speedtest.net on Firefox in the past but back then it was straight up crashes, not what is happening now.

I am on the latest Firefox version and I am unsure as to how long this problem may have been occurring because I haven't tried doing a speed test in quite some time.

Thank you.

I was trying to do a speedtest in FireFox and on speedtest.net, the font is wrong, when I do the download it stutters and lags before it gets to the final result. For example I have 350-400 down usually. speedtest.net for the download test will skyrocket and stutter to 330+, then stutter and skyrocket down to 120+ then to 200+ and then it will just end. Other speedtest sites such as Speakeasy.net and Fast.com are hit or miss if they will show an upload speed. Sometimes they show the upload 0, sometimes it works like it seems its supposed to. In Chrome and on my phone the tests all work just fine. Firefox seems to be having issues and I was curious if anyone else is experiencing these things or could shed some light. I have had problems with Speedtest.net on Firefox in the past but back then it was straight up crashes, not what is happening now. I am on the latest Firefox version and I am unsure as to how long this problem may have been occurring because I haven't tried doing a speed test in quite some time. Thank you.

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It would help if you show the issue. I'm in Win 11 and have no issues. Did you try the same steps with Firefox in Safe Mode? https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode#w_how-to-start-firefox-in-4troubleshoot-modesf5safe-modesf