>>10249
>use an extension to play MKV in a web browser
IDK, but this works:

<video controls width="300">
<source src=" https://cloudflare-ipfs.com/ipns/k51qzi5uqu5diwzufekv38cynmdqlh0lwic1ve0d9w5a0glpy52qjc0l77h4t5/1/QmW9eqNWiQ7xn5avGzquC8ZGE3DFcUPkUfWd9gkdiV4Bp5/Ariana_Chim_Chim_UC9DdUaW9lRyPcRJr7cUUBDw/No_Excuses_PMV_MLP-Ariana_Chim_Chim-20190714-youtube-1920x1080-eMb6L12Ey4E.mkv " type="video/mp4">
</video>

Can be ran in https://htmledit.squarefree.com/ - about that specific .mkv: I kinda like that pop music and video; video shows eqg

So that works in Chrome, but probably does not work with all MKVs as stated here: https://stackoverflow.com/questions/21192713/how-to-playback-mkv-video-in-web-browser - therefore, maybe try this:
https://github.com/ilian/mkv-web

It uses JavaScript+web assembly+whatever to play MKVs. Maybe it works on all MKVs and in all browsers. Reminds me of like Brianv's software which plays webms via JavaScript - likely used in 4chan because iPones can't play WebM in Safari.