Hello,
Youtube links on my instance of Discourse stops to embed video player (after 2.9.0.beta2 update).
It shows like static pictures with links to Youtube.
What should I check?
I know there was work done on the embed, so this might be a bug
@david can you help here please 
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Any errors in the browser console? Does the same thing happen here on meta if you use an identical YouTube link?
The problem was in this plugin Trading buttons: Buy, Sell, Exchange - #79 by Dmitry_Krasnoperov
I disabled it temporary. And YouTube works.
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