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Firefox 34 Breaks Flash Player

  • 4 replies
  • 124 have this problem
  • 3 views
  • Last reply by ellenjones6

user1150464
user1150464
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I have Flash Player 11.2.202.424 installed and it has been working perfectly. However, upgrading from Firefox 33 to 34 breaks Flash Player. It is still enabled according to about:plugins, but the test page http://www.adobe.com/software/flash/about/ no longer works and YouTube videos are now black boxes. Any help is appreciated. Thank you.

I have Flash Player 11.2.202.424 installed and it has been working perfectly. However, upgrading from Firefox 33 to 34 breaks Flash Player. It is still enabled according to about:plugins, but the test page http://www.adobe.com/software/flash/about/ no longer works and YouTube videos are now black boxes. Any help is appreciated. Thank you.

Chosen solution

Still works for me with Firefox 34.0.5

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

  • Switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance
  • Do NOT click the Reset button on the Safe Mode start window

Any luck with disabling OMTC?

You can try to disable OMTC and leave hardware acceleration in Firefox enabled.

  • about:config page: layers.offmainthreadcomposition.enabled = false

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.

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All Replies (4)

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

Still works for me with Firefox 34.0.5

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

  • Switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance
  • Do NOT click the Reset button on the Safe Mode start window

Any luck with disabling OMTC?

You can try to disable OMTC and leave hardware acceleration in Firefox enabled.

  • about:config page: layers.offmainthreadcomposition.enabled = false

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.

tagfoto
tagfoto
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The only real solution appears to be rolling back to a stable version. At work I had to use a prehistoric version of Sea Monkey today - FF worked until the last "upgrade." Ouch...a patched version would be useful.

Rudolfm
Rudolfm
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DO NOT CHANGE the above mentioned layers... in Android! I tried it and then about:config stopped functioning, and all I got was blank screens. I had to edit prefs.js using a filemanager with root rights to get Firefox back to working.

ellenjones6
ellenjones6
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My solution is to stop using Firefox until Firefox finds a fix for this problem.