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How do i stop firefox lagging/hanging momentarily (5-10 seconds) when i try and buffer a large video/application?

  • 4 replies
  • 11 have this problem
  • 8 views
  • Last reply by Bugz000

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Hello there,

when i try and buffer a large video (HD youtube) or for even more lag - run a speedtest

the animation for speedtest is in about 3 frames - about 4-6 seconds apart, as for youtube, it buffers about 2 seconds - then firefox hangs for about 12 seconds - when it comes back it's fully buffered

this issue has arose since i got new internet (76mbit download) and it is not my rig as both youtube and speedtest.net run perfectly smooth in chrome (but i don't like chrome or google's customer support)

i have already tried enabling/disabling hardware accelleration and tried a few tweaks - anything else you can suggest? (suggest any tweaks- i'll try anything)

i thank you for your time

Hello there, when i try and buffer a large video (HD youtube) or for even more lag - run a speedtest the animation for speedtest is in about 3 frames - about 4-6 seconds apart, as for youtube, it buffers about 2 seconds - then firefox hangs for about 12 seconds - when it comes back it's fully buffered this issue has arose since i got new internet (76mbit download) and it is not my rig as both youtube and speedtest.net run perfectly smooth in chrome (but i don't like chrome or google's customer support) i have already tried enabling/disabling hardware accelleration and tried a few tweaks - anything else you can suggest? (suggest any tweaks- i'll try anything) i thank you for your time

Chosen solution

You can check for problems caused by recent Flash updates and try these:

  • disable a possible RealPlayer Browser Record Plugin extension for Firefox and update the RealPlayer if installed
  • disable protected mode in Flash 11.3 and later
  • disable hardware acceleration in the Flash plugin
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The Reset Firefox feature can fix many issues by restoring Firefox to its factory default state while saving your essential information. Note: This will cause you to lose any Extensions, Open websites, and some Preferences.

To Reset Firefox do the following:

  1. Go to Firefox > Help > Troubleshooting Information.
  2. Click the "Reset Firefox" button.
  3. Firefox will close and reset. After Firefox is done, it will show a window with the information that is imported. Click Finish.
  4. Firefox will open with all factory defaults applied.


Further information can be found in the Refresh Firefox - reset add-ons and settings article.

Did this fix your problems? Please report back to us!

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this did not fix it - infact it made it worse as i have now lost all those tweaks i previously applied...

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Chosen Solution

You can check for problems caused by recent Flash updates and try these:

  • disable a possible RealPlayer Browser Record Plugin extension for Firefox and update the RealPlayer if installed
  • disable protected mode in Flash 11.3 and later
  • disable hardware acceleration in the Flash plugin
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i updated flash and disabled protected mode and it's running smooth now :) perfect, thankyou so much!