Watch page description below the video with proper open/close toggle, instead of a side bar.
< Feedback on YouTube - Proper Description
I can't replicate on my side.
It's just another A/B test from Youtube that only certain people get.
Until the test hits my account there's nothing I can do.
It's worth noting that the test could fail and this "feature" to not be implemented for everyone.
I love the extension, but can you make it so that it removes the "open in YouTube music" window? It stands out and also cuts the description off in the middle.