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Firefox crashing when playing video on Youtube (HTML5)

  • 2 replies
  • 1 has this problem
  • 8 views
  • Last reply by cor-el

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Latest version of Firefox for Mac OS X 10.11 crashes when playing Youtube video.

Symptoms: - Blocky Artifacts on the screen - Hard Lock up - Slow performance

Does not occur under Safari, or Chromium. Does not occur under old version of Firefox (v. 37).

Specs:

Mac Mini 2012 i7 processor 16 GB Memory 1TB HDD OSX 10.11 El Capitan

Latest version of Firefox for Mac OS X 10.11 crashes when playing Youtube video. Symptoms: - Blocky Artifacts on the screen - Hard Lock up - Slow performance Does not occur under Safari, or Chromium. Does not occur under old version of Firefox (v. 37). Specs: Mac Mini 2012 i7 processor 16 GB Memory 1TB HDD OSX 10.11 El Capitan

All Replies (2)

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Hello,

Can you please go through these help articles, some of the solution out ther may help you out.

Fix common audio and video issues

Please reply back for any help.

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In the current release Firefox might be using the HTML5 media player instead of a Flash based player in older Firefox versions.

You can try to set media.apple.mp4.enabled to false on the about:config page to see if that has effect. You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.