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certain web sites will not play video

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  • Dernière réponse par cor-el

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Recently migrated to Firefox from MS Edge. Now I can't watch videos on NHL.com and NFL.com. These just have black boxes where video should be. Bleacher report doesn't fill in all news feed article links, pictures etc. Other pages work fine with embedded video. You tube works. Did set up privacy extensions so not sure if there is a conflict with one of them. Any guidance is greatly appreciated.

Recently migrated to Firefox from MS Edge. Now I can't watch videos on NHL.com and NFL.com. These just have black boxes where video should be. Bleacher report doesn't fill in all news feed article links, pictures etc. Other pages work fine with embedded video. You tube works. Did set up privacy extensions so not sure if there is a conflict with one of them. Any guidance is greatly appreciated.

Solution choisie

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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Solution choisie

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}

more options

If you use extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) that can block content (Adblock Plus, NoScript, Disconnect, Ghostery, Privacy Badger, uBlock Origin) always make sure such extensions do not block content.

Firefox shows the shield icon at the left end of the location/address bar in case Content Blocking is blocking content.

  • click the shield icon for more details and possibly disable the protection

You can check the Web Console about what content is blocked


You can check the Web Console for possible error messages related to this issue.