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Firefox 74, 75, 76, videos flicker when bookmarks toolbar is visible/present

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

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Problem: videos do flicker. Especially visible on youtube with static background. Flicker is only present when video is playing, it doesn't flicker when video is stopped.

It doesn't flicker in safe mode. However, disabling every single addon and plugin I have and using default theme does nothing. Nor does enabling or disabling hardware acceleration.

What is this secret magic that safe mode have and unsafe mode doesn't?

Firefox 76.0.1, Ubuntu 18.04, Nvidia 440.82

UPD: figured out that this is happening only and every time when bookmarks toolbar is present O_o

Old subj was: Firefox 74, 75, 76, videos flicker when not in safe mode, tried everything, nothing helps

PS: how do I break a line here?

Modified by GG

All Replies (5)

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Hi GG, please ignore the fake support link someone is spamming here. A genuine community support volunteer will reply in this thread. https://support.mozilla.org/questions/1289045

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Hi GG, is the flickering only within the video player itself, or across the page?

I ask that because scripts in the YouTube page resize the player and rearrange elements on the page depending on the viewport area, which is affected by the toolbar height, i.e., more or fewer toolbars displayed. Sometimes there are "rounding errors" which might cause a ceaseless recalculation but I really have no idea whether that is relevant. Changing the zoom level one tick (Ctrl+ or Ctrl-) might change the math.

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Are you possibly using code in userChrome.css that could cause this?

Try the Firefox version from the official Mozilla server if you currently use a version from the repositories of your Linux distribution.

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jscher2000 said

is the flickering only within the video player itself, or across the page?

Only player, which is downsized slightly when bookmars toolbar is presend

cor-el said

Are you possibly using code in userChrome.css that could cause this?

I couldn't find a file with this name in my file system.

Does this mean I don't?

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A possible userChrome.css would be in the chrome folder in the Firefox profile folder.

You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.


What are the current Firefox window dimensions as it is possible that you are exactly on a point where an @media rule kicks in ?