[whatwg/dom] MutationObserver needs an equivalent of disconnected & connected callbacks (#533)

It would be useful to have a way of observing when a node gets connected or disconnected from a document similar to the way `connectedCallback` and `disconnectedCallback` work for custom elements but unlike those at the end of the microtask like all other mutation records.

-- 
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/whatwg/dom/issues/533