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Not launching external apps after update

N2rock2

My Firefox updated today to 58.0.2 (64 bit). After the update, it won't launch the external apps that I have set up. For example, I have it set to play mp4 files in quicktime (which is my default viewer). But now when I click on an mp4 link, it launches in the broswer. Same thing for mp3's. I have gone to the "options" to check that those options were still set to "use quicktime player". The update had changed those back to the Firefox settings, so I went ahead and reset them to quicktime. But even after making that change, the files are still launching within the browser.

My Firefox updated today to 58.0.2 (64 bit). After the update, it won't launch the external apps that I have set up. For example, I have it set to play mp4 files in quicktime (which is my default viewer). But now when I click on an mp4 link, it launches in the broswer. Same thing for mp3's. I have gone to the "options" to check that those options were still set to "use quicktime player". The update had changed those back to the Firefox settings, so I went ahead and reset them to quicktime. But even after making that change, the files are still launching within the browser.
從原來的回覆中察看解決方案

選擇的解決方法

You can set this pref to false on the about:config page to prevent Firefox from playing media files via the HTML5 media player.

  • media.play-stand-alone = false

所有回覆 (5)

Those are plugins.

Firefox v52+ disables all plugins except for Flash Why do Java, Silverlight, Adobe Acrobat and other plugins no longer work? {web link}

You can check prefs like these on the about:config page.

  • media.mediasource.mp4.enabled
  • media.apple.mp4.enabled
  • media.apple.mp3.enabled

You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.

cor-el said

You can check prefs like these on the about:config page.
  • media.mediasource.mp4.enabled
  • media.apple.mp4.enabled
  • media.apple.mp3.enabled
You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.

Thanks for the advice Here's what I have

  • media.mediasource.mp4.enabled - This is marked "true"
  • media.apple.mp4.enabled - This does not appear in my config
  • media.apple.mp3.enabled - This does not appear in my config

I do have a "media.mp4.enabled" (marked "true"). But nothing containing "mp3".

Everything is still playing in the browser instead of launching the associated app to play it.

選擇的解決方法

You can set this pref to false on the about:config page to prevent Firefox from playing media files via the HTML5 media player.

  • media.play-stand-alone = false

cor-el said

You can set this pref to false on the about:config page to prevent Firefox from playing media files via the HTML5 media player.
  • media.play-stand-alone = false

Thank you VERY much! That worked!