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Firefox cannot play video smoothly

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Every time I browse webpage by using Firefox, all the videos are jerky, lag and choppy. However, this never happen when I am using Chrome to play the videos. For example the video in TED.com is jerky in Firefox but smooth in Chrome and IE.

I searched all the solutions in this forum and tried all of them but none of them work. The solutions like turn off hardware acceleration, change adobe flash settings and update graphic drivers and etc do not work on my laptop.

Even in Firefox safe mode the videos cannot be played smoothly, so I am sure this is not caused by the extensions I had installed.

Every time I browse webpage by using Firefox, all the videos are jerky, lag and choppy. However, this never happen when I am using Chrome to play the videos. For example the video in TED.com is jerky in Firefox but smooth in Chrome and IE. I searched all the solutions in this forum and tried all of them but none of them work. The solutions like turn off hardware acceleration, change adobe flash settings and update graphic drivers and etc do not work on my laptop. Even in Firefox safe mode the videos cannot be played smoothly, so I am sure this is not caused by the extensions I had installed.

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Hello Try to disable Protected Mode in Flash 11.3 and above by adding the line ProtectedMode=0 to the Flash "mms.cfg" file located in one of these locations: [46]

  (Windows 32bit) C:\Windows\System32\Macromed\Flash 
  (Windows 64bit) C:\Windows\SysWOW64\Macromed\Flash 

For example, on a Windows 7 64-bit system, open the C:\Windows\SysWOW64\Macromed\Flash folder, copy the file "mms.cfg" to the desktop, open it in Notepad, add a new line ProtectedMode=0 and then close Notepad, saving your changes. Next, go back to the C:\Windows\SysWOW64\Macromed\Flash folder, rename the original file to "mms.cfgBAK" (to save it as a backup) and then drag and drop in the modified "mms.cfg" file from the desktop. [47] [48] [49]

Note: To re-enable Flash Protected Mode, either restore a backup of the original mms.cfg file, if you saved one, or else re-edit the mms.cfg file to remove the ProtectedMode=0 l line you added. Updating Flash Player or installing a newer version does not automatically re-enable Protected Mode

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In Windows Vista and Windows 7 and later you can toggle this pref to true on the about:config page to disable protected mode in the Shockwave Flash plugin, so it is no longer needed to modify the mms.cfg file in Firefox 36 and later.

  • dom.ipc.plugins.flash.disable-protected-mode = true

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.

See also: