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Embedded videos shows black screen

Firefox Troubleshooting
cor-el replied
martin_wanderer
martin_wanderer

Some embedded videos work only in Safe Mode but show black rectangle otherwise. I have read similar questions like https://support.mozilla.org/en-US/questions/1044374. Already tried removing all extensions and themes, disabling hardware acceleration, refreshing Firefox and even reinstalling ( with apt purge firefox and removing ~/.mozilla, /etc/firefox and /usr/lib/firefox*) and disabling acceleration again. Example page: https://ru-chp.livejournal.com/13903492.html

As far as I can see there's just no
element when not in Safe Mode.
Some embedded videos work only in Safe Mode but show black rectangle otherwise. I have read similar questions like https://support.mozilla.org/en-US/questions/1044374. Already tried removing all extensions and themes, disabling hardware acceleration, refreshing Firefox and even reinstalling ( with apt purge firefox and removing ~/.mozilla, /etc/firefox and /usr/lib/firefox*) and disabling acceleration again. Example page: https://ru-chp.livejournal.com/13903492.html As far as I can see there's just no <div class="videoplayer"...> element when not in Safe Mode.

All Replies (4)

martin_wanderer
martin_wanderer Question owner
  • As far as I can see there's just no div class="videoplayer" element when not in Safe Mode.

P.S. we have rather aggressive markup filter here

cor-el
cor-el
  • Moderator
  • Top 10 Contributor

Chosen Solution

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

  • "3-bar" menu button or Tools -> Web Developer

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 an highlighted shield icon at the left end of the location/address bar in case Tracking Protection 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

martin_wanderer
martin_wanderer Question owner

Thank you. It's Cross-Site Tracking Cookies. Is there way to allow cross-site tracking for particular third-party cookies without turning tracking protection off?

cor-el
cor-el
  • Moderator
  • Top 10 Contributor

You can try to create a cookie allow exception for involved third-party domains.