bugfix: On Preact, sometimes DOM & Slate selection are mismatching

[Jabher]

Description
Sadly, I cannot create stand-alone reproduction environment, only happens in real world for me.

When switching between multiple editors quickly, there is around 5% chance of following error (location differs):

Uncaught (in promise) Error: Cannot resolve a DOM point from Slate point: {"path":[1,0],"offset":6}

which is caused by this line:
https://github.com/ianstormtaylor/slate/blob/main/packages/slate-react/src/components/editable.tsx#L217

No idea why this only happens on real-world, but I was not able to reproduce this behavior on some demo stage.
However, the environment is the following:

• Slate 0.72.3, Slate-React 0.72.1
• Plate 7.x
• Preact 10.5.4
• 2 or more editors are present on a same page

Due to fact it is not happening every time, looks like this is race-condition problem and incompatibility between slate and (possibly) preact. However, this logic fully fixes everything.

Checks

• The new code matches the existing patterns and styles.
• The tests pass with yarn test.
• The linter passes with yarn lint. (Fix errors with yarn fix.)
• The relevant examples still work. (Run examples with yarn start.)
• You've added a changeset if changing functionality. (Add one with yarn changeset add.)

[changeset-bot]

🦋 Changeset detected

Latest commit: 0fedd28

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
slate-react	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[dylans]

Seems like a reasonable check that won't slow things down or cause harm. Let me know when it's ready for a real review and remember to add a changeset when you're ready.

[Jabher]

Sure! just wanted to check every thing possible

[Jabher]

@dylans Hi! Everything is ready, tests are fine... sadly I was not able to figure out how to make stable test that reproduces this behavior. However, all the tests are running fine

[dylans]

Thanks @Jabher . I'm thinking this may also help fix #4789 and other similar issues.

[Jabher]

was happy to help!

[BitPhinix]

Sadly this change causes issues for us, checking if the selection is set and in the editor at this stage results in slate-react not updating the selection if it isn't already inside the editor. So focusing and selecting something without having a dom selection (or selection inside the editor) doesn't update/set the dom selection.

[BitPhinix]

@dylans could you revert it? There has to be another way to solve this issue, as this pr breaks basic slate functionality.

[dylans]

@dylans could you revert it? There has to be another way to solve this issue, as this pr breaks basic slate functionality.

Done, will release as soon as the CI finishes.

[BitPhinix]

Awesome, thanks so much 👍