Youtube: Your browser can't play this video Topic is solved

[Tharthan]

Are there any Pale Moon settings that might cause this to happen for "non-DRM" (or should be non-DRM) livestreams?

I've just tested viewing (after noticing that it was doing this for one particular livestream) a number of livestreams on YouTube, and it gives me this message for all of them.

Off-topic:
It does something very similar on Twitch.tv (even when logged in) for me, showing a light purple question mark with a small square adjacent to each corner, instead of the actual livestreamed video.

Crucially, this does not happen for me on either website when viewing previously-recorded livestreams, videos, or clips. Only the livestreams that are currently in progress.

[Moonchild]

Looks like Twitch started to require MediaCapabilities. This is a very controversial and highly fingerprintable API that is sideways related to DRM. Basically it exposes to the web detailed media (video/audio) decoding and encoding capabilities.
We don't support it currently.

[suzyne]

Can confirm. Tried turning off the Hardware Acceleration and uBlock Origin, and the problem persists.

[Deadgye]

Looks like Twitch started to require MediaCapabilities. This is a very controversial and highly fingerprintable API that is sideways related to DRM. Basically it exposes to the web detailed media (video/audio) decoding and encoding capabilities.
We don't support it currently.

I'm not sure it's that. I used https://player.twitch.tv/?parent=www.tw ... NUMBERHERE to get the embedded player and the video works while the browser console still logs the same "MediaCapabilities is not supported", "MediaCapabilities found Array [ Object, Object, Object, Object, Object ]", and "Unhandled promise rejection" messages you'd see logged from the normal site.

Based on other recent complaints that twitch broke, and what fixed it for them, I'm going to guess the actual issue might be https://repo.palemoon.org/MoonchildProd ... ssues/2473

[adoxa]

It does indeed seem to be :has at issue for twitch; here's a userstyle workaround.

Code: Select all

@-moz-document domain("www.twitch.tv") {
  .persistent-player {
    width: 100%
  }
}

[Moonchild]

Ah well that's better then. I'd really prefer to avoid the MediaCapabilities API if at all possible.

[Tharthan]

It does indeed seem to be :has at issue for twitch; here's a userstyle workaround.

Code: Select all

@-moz-document domain("www.twitch.tv") {
  .persistent-player {
    width: 100%
  }
}

How does one use that?

Also, has it been determined whether something similar might be happening with YouTube for streams in any way?

[Moonchild]

How does one use that?

You can put it in UserContent.css in your profile's chrome subfolder, and restart the browser to pick it up.

[Deadgye]

Off-topic:
Adding an additional confirming that the CSS style fixed twitch's player for me.
I also made a thread to separate the twitch player issue from this thread.

Also, has it been determined whether something similar might be happening with YouTube for streams in any way?

The issue with twitch's player on twitch.tv is unrelated. To recap the thread: Youtube videos and streams should work on Pale Moon, notwithstanding channels that require specific DRM libs--such as google's widevine DRM--like the channel in OP's post.

[moonbat]

How does one use that?

Or use Stylem, which is easier for CSS tweaks.