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Speedtest.xfinity.com works on Chrome but hasn't worked on Firefox for years.

  • 10 ردود
  • 1 has this problem
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  • آخر ردّ كتبه charley000

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I check my Internet speed by using speedtest.xfinity.com It works fine on Chrome. On Firefox it starts but hang at about 55% and never completes. I have been having this problem on and off for several years. I have tried disabling add-ins, etc.

I check my Internet speed by using speedtest.xfinity.com It works fine on Chrome. On Firefox it starts but hang at about 55% and never completes. I have been having this problem on and off for several years. I have tried disabling add-ins, etc.

All Replies (10)

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I had no problem with the link.

Many site issues can be caused by corrupt cookies or cache.

Warning ! ! This will log you out of sites you're logged in to. You may also lose any settings for that website.

If there is still a problem, Start Firefox in Safe Mode {web link} by holding down the <Shift> (Mac=Options) key, and then starting Firefox.

A small dialog should appear. Click Start In Safe Mode (not Refresh). Did this help?

While you are in safe mode;

Try disabling graphics hardware acceleration in Firefox. Since this feature was added to Firefox it has gradually improved but there are still a few glitches.

How to disable Hardware Acceleration {web link}

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I have done all those things but just to check I did them again now. Still doesn't work. When I go to speedtest.xfinity.com, I get there and I start the test. But somewhere typically around 55% done it just hangs. Works perfectly on Chrome.

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To add more to the strange behavior, I tried turning off my firewall and that made no difference. It doesn't work at all on IE. Almost finishes on Edge. As I said, works perfectly on Chrome. But never finishes on Firefox.

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Start your Computer in safe mode with network support. Then start Firefox. Try Secure websites. Is the problem still there?

http://encyclopedia2.thefreedictionary.com/Linux+Safe+Mode Starting Any Computer In Safe Mode; Free Online Encyclopedia

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Same issue in Safe Mode. I can access all sites. Everything works except speedtest.xfinity.com hangs in the middle of the test.

I usually use Chrome for the speed tests because speed was about double what I would get from Firefox. And Firefox would often hang up for a bit in the middle of the test and then complete. But now it just gets stuck and never finishes.

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Unplug your modem/router and anything else that connects you to the web. Wait for a slow count of 15. Then try again.

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Boot the computer in Windows Safe mode with network support to see if that has effect in case security software is causing problems.

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I have done all those things. My network works fine (I get almost 500 mbps down but only 12 mbps up due to Comcast rate limiting the upstream).

Firefox hangs on speedtest.xfinity.com. Speed tests from other sites (speedtest.net, dslreports.com, etc.) work fine on Firefox. It is something to do with Firefox and Xfinity.

It used to work but always gave me speeds about 1/2 the speed I would get with Chrome. But now Firefox hangs part way through the test.

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Contact your ISP and ask about this.

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Fred, it's not my ISP. It is a Comcast speed test problem. They apparently have some kind of strange bug in their speed test, probably a javascript issue. I found a Comcast forum that discusses it. However, if it works on Chrome, it should work on Firefox!