I thought it might be cool (if it were possible) to also have the automatic youtube play@time function when a user replies with an arbitrary time say 0:45. Not sure if it is possible for embedded videos but it’s just a thought. I would imagine it may be possible with some js though? And if many videos are posted, I guess the original post should be replied to directly so the time is linked to the right video. If there are multiple videos in one post however, well, I don’t know. Just thoughts out on a line. Super nit-picky feature but thought I’d share 
This is now implemented for the URLs you get from the Share box:
https://github.com/discourse/onebox/commit/8a11f30e5095813ed9969163a2b153d8d6abfeb3
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