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videos wont play on various web sites

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Since my upgrade to FF 29, videos on certain web sites will not play. I have tried disabling any and all potential ad blocking, ghostery, and various plug ins to no avail. I say various because as long as I am visiting a video hosting site such as YouTube, there are no problems. Seems that any site that has a video that displays their content won 't play. I have also tried allowing 3rd party cookies and pop ups. I'm running out of ideas. Have you any ideas??

Since my upgrade to FF 29, videos on certain web sites will not play. I have tried disabling any and all potential ad blocking, ghostery, and various plug ins to no avail. I say various because as long as I am visiting a video hosting site such as YouTube, there are no problems. Seems that any site that has a video that displays their content won 't play. I have also tried allowing 3rd party cookies and pop ups. I'm running out of ideas. Have you any ideas??

Chosen solution

Note that you have a few extensions that can block content or cookies or otherwise interfere with retrieving data

  • If you have many extensions then first enable half of the extensions to test which half has the problem.
  • Continue to divide the bad half that still has the issue until you find which one is causing it.

It is also possible that web pages use a <video> tag to use a HTML5 media player.

You can disable this media player by setting these prefs to false on the about:config page.

  • media.windows-media-foundation.enabled
  • media.directshow.enabled
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All Replies (3)

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The issue could be caused by one of your add-ons. Restart Firefox with Add-ons Disabled to check if that's the case.

If the problem goes away in Safe Mode, you can either try to determine which add-on is to blame, or you can Reset Firefox and get rid of them all.

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Chosen Solution

Note that you have a few extensions that can block content or cookies or otherwise interfere with retrieving data

  • If you have many extensions then first enable half of the extensions to test which half has the problem.
  • Continue to divide the bad half that still has the issue until you find which one is causing it.

It is also possible that web pages use a <video> tag to use a HTML5 media player.

You can disable this media player by setting these prefs to false on the about:config page.

  • media.windows-media-foundation.enabled
  • media.directshow.enabled
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The issue is resolved. The problem is 1 of 4 add ons that block Google tracking. That being the case, I do not need to see any video that Google needs to track.

Thank you so much everyone. Let's all keep Google from meddling. It's no one's business what I look at or what sites I visit. And, I'm not in the 18 to 34 yo age group and therefore am not a "consumer" that needs ads.

edit: removed attached picture (philipp)

Modified by philipp