@dontcallmedom is this an amendment or an editorial? Inside webrtc-pc, this dictionary is only used as output meaning it doesn't change any behavior. But in webrtc-extension we start taking this dictionary as input, and do care about "required"

it's very much in the gray zone; I would err on the side of being conservative and document it as an amendment.

OK. I'm unfamiliar with the amendment process - should I do something to unblock this PR?

I'll take care of it

Thanks! Can I merge now?

Good to go from my perspective