I've been using this format for, I have no clue, 25 years? Longer? What took them so long?
this post was submitted on 11 Sep 2025
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I don't think the reason was technical. Firefox has supported WebM (a subset of Matroska) for 11 years, and whatever code they had probably would have been enough for most Matroska files, assuming the codecs are also supported.
However, Matroska itself was only officially standardised last October despite being in use all these years. That was probably what convinced them to add support.
Prioritization probably.
They are busy keeping up with engineering teams 4x their size for their browser competition.... (~500 engineers building Firefox vs ~2000 building chrome)
Of a million potential features, you can only choose a subset to work on. This one was likely low impact and a low enough use case priority that it got regularly bumped under higher priority work.
This is just the way... Well... Anything with limited resources works.
Happy they finally got around for this.
The AI Epic has so much higher priority, you know?
It's what ~~plants~~ CEOs crave!
probably licensing.
It's open standard. No license is required.
fair enough, i didn't look it up.
Seems important
It's more than important. It's vital to me. I host TV series ripped from discs on my NAS through HTTP and play them back on another machine.
For years I used an extension which sends the URL to VLC for playback via HTTP. Nowadays I got rid of the extension and just drag and drop. That doesn't mark the link as clicked, though. It's hard to track the progress this way.
Ever thought about using a media server like Jellyfin?
I wonder if this will help improve playback on Firefox when using Jellyfin. Maybe it will be able to play more directly and use less server resources, my NAS has relatively modest power.
Plex (I know) with their native app works very well.
Oh, Jellyfin works, don't get me wrong (and it has native apps too). But I welcome every little performance gain. The NAS already starts getting noisy even when it runs just simple docker images on idle.. it can get a bit annoying.
And, from what I heard, Plex tends to have a more resource-intensive idle state due to having more cloud-based features and background tasks.
It feels like using a browser to play video always take wayyyy more resource than a video player. Sending a link to vlc seems like an optimal option to me.
You are not wrong. However, how did MP4 get supported in the first place? Before 2010s, the expected user behaviour was still downloading an MP4 and play with a native player. Why the big gap between MP4 support and MKV support?
How is that vital?
Let's just say there were times I opened the browser after a long day of work just to enjoy an episode or two to prevent mental breakdown.
Wish they would add support for HEVC
It's been a long time since I came across matroska files in numbers, but this is pretty cool to have.
Probably now all or almost all of the videos on my PC are in MKV format. It's codecs of that files well it's a story for another day
I still need MP4, because lot of programs or services don't accept or understand MKV unfortunately. I don't know all the differences, but I know that MKV is better for live recording, because if its stopped abruptly the file is still usable. Some little websites I upload little meme mp4 files (in place of GIF) would not accept MKV too. So I'm stuck.