We're calling on all EU-based Mozillians with iOS or iPadOS devices to help us monitor Apple’s new browser choice screens. Join the effort to hold Big Tech to account!

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

WebM Video is reported as unsupported

  • 8 replies
  • 3 have this problem
  • 2 views
  • Last reply by OniLinkPlus

more options

Every single WebM file I try to play (and I have tried MANY, all of which work in Chrome, VLC, etc., but not Fireofx) is reported by Firefox to be "corrupt". Gfycat doesn't work unless I switch to gif mode because the only two video formats Gfycat stores files as are MP4 which is apparently unsupported by Firefox due to patents and WebM which is where my problem lies. Youtube's HTML5 player doesn't work either. It just sits on the loading circle forever, refusing to go anywhere because apparently Firefox doesn't support WebM. I have tried disabling all addons and extensions and restarting Firefox and it did nothing. I distinctly remember WebM working in the distant past, and when I go to websites such as html5test and the page to activate Youtube's HTML5 player, they all report that my browser supports WebM, but no WebM videos actually work.

Every single WebM file I try to play (and I have tried MANY, all of which work in Chrome, VLC, etc., but not Fireofx) is reported by Firefox to be "corrupt". Gfycat doesn't work unless I switch to gif mode because the only two video formats Gfycat stores files as are MP4 which is apparently unsupported by Firefox due to patents and WebM which is where my problem lies. Youtube's HTML5 player doesn't work either. It just sits on the loading circle forever, refusing to go anywhere because apparently Firefox doesn't support WebM. I have tried disabling all addons and extensions and restarting Firefox and it did nothing. I distinctly remember WebM working in the distant past, and when I go to websites such as html5test and the page to activate Youtube's HTML5 player, they all report that my browser supports WebM, but no WebM videos actually work.

All Replies (8)

more options

Have you got an example of a site which doesn't work for you?

All formats on this test page work fine here. http://www.quirksmode.org/html5/tests/video.html

Make sure you have Javascript allowed.

more options

Only OGG Theora works on that page. The other two say "No video with supported format and MIME type found." Javascript is allowed.

more options
more options

I tried everything in that thread one at a time and nothing worked.

more options

WebM should work in Firefox if it is enabled.

  • about:config page: media.webm.enabled = true

H.264 should work on Linux if you have GStreamer support installed.

  • about:config page: media.gstreamer.enabled = true
more options

You would think so, but both are enabled and neither works. Screenshots attached as evidence.

more options

VLC shows this for me:

Codec: Google/On2's VP8 Video (VP80)

Codec: H264 - MPEG-4 AVC (part 10) (avc1)

more options

I don't know what happened, but I was looking through settings, rebooted Firefox, and suddenly H.264 video works. WebM still doesn't work unfortunately, and that's what I need working.