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Videos only show the upper left-hand portion of the image when playing.

  • 4 replies
  • 15 have this problem
  • 17 views
  • Last reply by Ed

canyonlight
canyonlight
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When I attempt to play a video in Firefox (23.0) on my Mac, all I can see is the upper left-hand fourth of the video image.

When I attempt to view the same video in Safari it works fine. The entire image is rendered.

Mac OS X 10.8.4

When I attempt to play a video in Firefox (23.0) on my Mac, all I can see is the upper left-hand fourth of the video image. When I attempt to view the same video in Safari it works fine. The entire image is rendered. Mac OS X 10.8.4

Chosen solution

Hello,

There are a couple of things that might be causing this. Please can you try the following:

  • Check that Adobe Flash plugin is updated to the latest version
  • Open Firefox in Safe Mode and check whether the problem repeats. If not then most likely an add-on is causing the issue.
  • Try disabling Hardware Acceleration - Options>Advanced>General> Untick 'Use Hardware Acceleration when available'
  • Try disabling 'protected mode' in flash player or rolling back to Flash player 11.2. See this support thread for details: Flash video only showing a quarter...

I hope that helps. If not then I would try a Firefox Reset. This will return Firefox to it's default settings but will keep your browser history, bookmarks etc.

Read this answer in context 👍 3

All Replies (4)

Ed
Ed
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Chosen Solution

Hello,

There are a couple of things that might be causing this. Please can you try the following:

  • Check that Adobe Flash plugin is updated to the latest version
  • Open Firefox in Safe Mode and check whether the problem repeats. If not then most likely an add-on is causing the issue.
  • Try disabling Hardware Acceleration - Options>Advanced>General> Untick 'Use Hardware Acceleration when available'
  • Try disabling 'protected mode' in flash player or rolling back to Flash player 11.2. See this support thread for details: Flash video only showing a quarter...

I hope that helps. If not then I would try a Firefox Reset. This will return Firefox to it's default settings but will keep your browser history, bookmarks etc.

Modified by Ed

canyonlight
canyonlight Question owner
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Did a Firefox Reset. That did it. Thanks so much!

Andjar
Andjar
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I have this problem too, but only on my MBP with retina display. When I move the Firefox window to the attached external (non-retina) display, the full video is visible. And moving the FF window back, 3/4 of the video disappear again...

  • I run the latest version of the Adobe Flash plugin (11,8,800,94 )
  • running FF in 'Safe Mode' doesn't solve the problem
  • 'Use Hardware Acceleration when available' is not checked
  • apparently there's no 'protected mode' for FF an Flash on OS X

A Firefox Reset is not an acceptable solution for me.

Any other hints how I could try to solve this problem?

Ed
Ed
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Hi Andjar,

It sounds like your issue is slightly different to canyonlight's.

Please start a new support thread for your question.

Thanks.