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Not launching external apps after update

  • 5 replies
  • 3 have this problem
  • 6 views
  • Last reply by N2rock2

N2rock2
N2rock2
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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.

Chosen solution

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
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All Replies (5)

FredMcD
FredMcD
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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}

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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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.

N2rock2
N2rock2 Question owner
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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.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
more options

Chosen Solution

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
N2rock2
N2rock2 Question owner
more options

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!