This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

What can I do to stop Firefox from lagging on movies like on youtube?

  • 4 replies
  • 21 have this problem
  • 1 view
  • Last reply by kobe

more options

I normally have quite a lot of lag when I'm watching movies on youtube or (for the dutch people) dumpert. When I use another browser to watch the video, I don't have any lag at all.

I normally have quite a lot of lag when I'm watching movies on youtube or (for the dutch people) dumpert. When I use another browser to watch the video, I don't have any lag at all.

All Replies (4)

more options

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!

more options

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

Try to disable hardware acceleration in Firefox.

more options

Update your graphic card driver.

My graphic card is a Geforce and the problem was fix after the update installation and a computer reboot.

Modified by dan0995

more options

Check if this issue is with other browsers too.