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Facebook videos won't play on FireFox

  • 3 replies
  • 1 has this problem
  • 1 view
  • Last reply by KrA40n1

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When I try to play any video it does not play. I can view the thumbnail and the play button but pressing it just loads for a while and then it shows the same (thumbnail and play button).

I am using Windows 10 and after recent updates that I had this started happening. I have checked that: - I can play YT videos - I can play both flash videos and games - It does not work on FireFox and Edge but it works on Chrome And I have tried: - Updating FireFox - Updating Adobe Flashplayer - Refreshing FireFox - Installing the Media feature pack for Windows - Starting FireFox with Add-ons disabled - Disabled "Use hardware acceleration where available" - Reconfigured FireFox in Windows Defender Firewall with its plugin container - Tried to untick "Block dangerous and intrusive content" - Checked if Facebook is blocked by Adobe Flash Player and allowed it everywhere - Tried to ipconfig -flushdns - Deleted my additional entries in the hosts file of Windows(although they have nothing to do with videos or Facebook)

I am out of ideas now so please give me any possible support.

When I try to play any video it does not play. I can view the thumbnail and the play button but pressing it just loads for a while and then it shows the same (thumbnail and play button). I am using Windows 10 and after recent updates that I had this started happening. I have checked that: - I can play YT videos - I can play both flash videos and games - It does not work on FireFox and Edge but it works on Chrome And I have tried: - Updating FireFox - Updating Adobe Flashplayer - Refreshing FireFox - Installing the Media feature pack for Windows - Starting FireFox with Add-ons disabled - Disabled "Use hardware acceleration where available" - Reconfigured FireFox in Windows Defender Firewall with its plugin container - Tried to untick "Block dangerous and intrusive content" - Checked if Facebook is blocked by Adobe Flash Player and allowed it everywhere - Tried to ipconfig -flushdns - Deleted my additional entries in the hosts file of Windows(although they have nothing to do with videos or Facebook) I am out of ideas now so please give me any possible support.

All Replies (3)

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Error: The manifest specifies content that cannot be displayed on this browser/platform. MVAFsZjioDC.js:321:371 Cannot play media. No decoders for requested formats: video/mp4; codecs="avc1.4d401e", video/mp4; codecs="avc1.4d401f", video/mp4; codecs="avc1.4d401e", video/mp4; codecs="avc1.42E01E mp4a.40.2", video/mp4; codecs="avc1.4D401E mp4a.40.2", video/mp4; codecs="avc1.4D401F mp4a.40.2", video/mp4; codecs="avc1.640032 mp4a.40.2", video/mp4; codecs="avc1.640033 mp4a.40.2", video/mp4; codecs="avc1.4d401e", video/mp4; codecs="avc1.4d401e", video/mp4; codecs="avc1.4d401f", video/mp4; codecs="avc1.4d401f", video/mp4; codecs="avc1.4d401f", audio/mp4; codecs="mp4a.40.5", video/mp4; codecs="avc1.42E01E mp4a.40.2", video/mp4; codecs="avc1.4D401E mp4a.40.2", video/mp4; codecs="avc1.4D401F mp4a.40.2", video/mp4; codecs="avc1.640032 mp4a.40.2", video/mp4; codecs="avc1.640033 mp4a.40.2", video/mp4; codecs="avc1.4d401e", video/mp4; codecs="avc1.4d401e", video/mp4; codecs="avc1.4d401e", video/mp4; codecs="avc1.4d401f", video/mp4; codecs="avc1.4d401f", audio/mp4; codecs="mp4a.40.5", video/mp4; codecs="avc1.42E01E mp4a.40.2", video/mp4; codecs="avc1.4D401E mp4a.40.2", video/mp4; codecs="avc1.4D401F mp4a.40.2", video/mp4; codecs="avc1.640032 mp4a.40.2", video/mp4; codecs="avc1.640033 mp4a.40.2", video/mp4; codecs="avc1.4d401e", video/mp4; codecs="avc1.4d401e", video/mp4; codecs="avc1.4d401e", video/mp4; codecs="avc1.64001f", audio/mp4; codecs="mp4a.40.5", video/mp4; codecs="avc1.42E01E mp4a.40.2", video/mp4; codecs="avc1.4D401E mp4a.40.2", video/mp4; codecs="avc1.4D401F mp4a.40.2", video/mp4; codecs="avc1.640032 mp4a.40.2", video/mp4; codecs="avc1.640033 mp4a.40.2", video/mp4; codecs="avc1.4d401f", video/mp4; codecs="avc1.4d401e", video/mp4; codecs="avc1.42c01e", video/mp4; codecs="avc1.4d401e", video/mp4; codecs="avc1.4d401e", audio/mp4; codecs="mp4a.40.5", video/mp4; codecs="avc1.42E01E mp4a.40.2", video/mp4; codecs="avc1.4D401E mp4a.40.2", video/mp4; codecs="avc1.4D401F mp4a.40.2", video/mp4; codecs="avc1.640032 mp4a.40.2", video/mp4; codecs="avc1.640033 mp4a.40.2" www.facebook.com perf_trace {"name": "e2e", "parent": "PageEvents.AJAXPIPE_ONLOAD"} Lkf4qpXGRyt.js:6:3469 Error: The manifest specifies content that cannot be displayed on this browser/platform. MVAFsZjioDC.js:321:371

This is what I get in the Web Console

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How was your FF installed? When you did this was all older FF uninstalled and Mozilla folders deleted prior to the update.

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No, FireFox was installed before the update and I have re-installed it at least 2 months ago(still after the re-install I think FB videos were working)