SolvedYouTubeCenter Video doesn't start.

As you can see in the image, the video doesn't start, there's only a black window appearing where the video should be.

I'm using: Firefox Quantum 60.0b11 (64-bit) and Youtube Center Developer version with greasemonkey.

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24 Answers

✔️Accepted Answer

Quick fix is to change the way window.matchMedia is getting overridden.
I'm running one of the dev builds for Chrome, here's what I did:
There are two spots in YouTubeCenter.js where window.matchMedia gets set to null. This needs to be changed to instead set to a function that returns false.
For me, I changed line 11061 from:

          window.matchMedia = null;

to:

          window.matchMedia = function(){return false;};

And line 26853 from:

	  injectScript(function(){ window.matchMedia = null; }, "matchMediaOverride.js");

to:

	  injectScript(function(){ window.matchMedia = function(){return false;}; }, "matchMediaOverride.js");

Other Answers:

If I wasn't extremely sick and had the energy to do more than just watch YT, I'd format a proper PR or upload fixed builds or something. But I'll leave that to someone that's not currently hacking up their lungs.
For those who can manage to apply the fix themselves, enjoy.

@valarnin: Thank you Thank you!

YeP is working on new YT script, gonna take a while but he's on the new project.

Cloning the repo to make the change. Jesus! This thing is 1.5GBs! lol. No wonder no one's made a pull request yet.

Anyways, here's the pull request: #2482

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