Re: [w3c/webcomponents] Add Scoped CustomElementRegsitry explainer (#865)

@annevk 
> It seems better to track documents than shadow roots so that the ordering within a document is the same as with the global registry

Naively, it seems like a potential advantage of and disadvantage of scoped registries is perf:
- A potential improvement i that skipping a shadow-including document tree walk when you have a registry associated with a single shadow root seems like a nice perf win.
- A potential downside is if pages start having a lot of registries (1 per element definition x 100s of definitions) then scoped registries could drastically increase the number of walks.

On my team we have definitely seen registration cost as a problem in very WC-heavy pages (100s of definitions) and devised ways to delay registration to improve first paint.

-- 
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/w3c/webcomponents/pull/865#issuecomment-700141069