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Firefox will not load any flash video, on any website.

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Hello, just recently firefox decided to stop loading flash video. Eg. Youtube, metacafe, etc. I tired uninstalling flash and reinstalling it, uninstalling firefox and reinstalling it, ive also tried scanning for viruses, and nothing has worked. Sometimes it will load the advertisement for youtube videos but thats it, after that it just stays black and the controls for the player still work as normal, but there is no video or audio. I've tried to install a different browser to see if that would make a difference and it did, i can view flash videos on chrome but the moment i go back to firefox, videos dont work anymore.

Hello, just recently firefox decided to stop loading flash video. Eg. Youtube, metacafe, etc. I tired uninstalling flash and reinstalling it, uninstalling firefox and reinstalling it, ive also tried scanning for viruses, and nothing has worked. Sometimes it will load the advertisement for youtube videos but thats it, after that it just stays black and the controls for the player still work as normal, but there is no video or audio. I've tried to install a different browser to see if that would make a difference and it did, i can view flash videos on chrome but the moment i go back to firefox, videos dont work anymore.

All Replies (3)

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Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the extensions or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox (Tools) > Add-ons > Appearance/Themes).


Your More system details list shows some modified network.http prefs that do not have the default value.
Try to disable HTTP pipelining and reset all user set network.http prefs via the right-click context menu to their default values.


To open the about:config page, type about:config in the location (address) bar and press the "Enter" key, just like you type the url of a website to open a website.
If you see a warning then you can confirm that you want to access that page.

  • Use the Filter bar at to top of the about:config page to locate a preference more easily.
  • Preferences that have been modified show as bold (user set).
  • Preferences can be reset to the default via the right-click context menu if they are user set
  • Preferences can be changed via the right-click context menu: Modify (String or Integer) or Toggle (Boolean)
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I tried what you said, some videos load faster now, but it still does the same thing. Ive tried loading firefox in safe mode with the same results. Also it looks like its trying to download the whole video before it actually starts to play it. Ive got a screenshot uploaded, for further info.

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Ok well, i went to youtube again, tried to load a video, and it stays black for a long time then it starts playing, so im pretty sure its downloading it completely before it starts playing it. Any ideas?