Shadow DOM support v2.x

[diervo]

I'm opening a new issue as all other Shadow DOM issues seem to have been closed as completed and it's unclear what the state o of the art currently is after 2.x release.

I just instanciated Quill inside shadow-dom (theme:snow) and some of the most basic operations like writing text seem buggy as the cursor/selection goes to the wrong places, and basic toolbar options don't seem to work out of the box.

I'm happy to help with some PRs/support to enable this, but if someone can provide me a summary of where things are or known bugs/gaps would be very valuable to see how much effort might take.

Platforms:
Latest Chrome

Version:
v2.0.1

[TechQuery]

Try my test PR: #2021 (comment)

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And list some Shadow DOM bugs:

1. Support Shadow DOM v1 #2021
2. Quill doesn't listen to modules when used with custom elements and shadow dom #3879
3. Quill inside shadow dom ignores passed options #4033

[tylerc]

After some testing, I found at least 3 issues: #4250

So I'd say it definitely isn't supported yet.