Collab: Active RichText formats can reset unexpectedly

[mirka]

Active RichText formats (like bold, italics, inline code) can be deactivated when a peer edit comes in, or if there is a peer caret in the same block.

Steps to reproduce

1. In one client, hit the Bold button and start typing in bold.
2. On the other client, type something in a different block.
3. Go back to the other client, and it's not in Bold mode anymore.

CleanShot.2021-09-15.at.01.04.47.mp4

[mirka]

The problem occurs when this returns a new object while the self caret is within an active format.

isolated-block-editor/src/components/collaborative-editing/use-yjs/formats/collab-caret/index.js

Lines 157 to 167 in 9a044ac

	// The properties in this return object need to be as stable as possible.
	// See https://github.com/WordPress/gutenberg/issues/23428
	return {
	carets: getCarets( select( 'isolated/editor' ).getCollabPeers(), richTextIdentifier, blockClientId ),
	multilineTag,
	blockAttributeSelector: getStableBlockAttributeSelector(
	select( 'core/block-editor' ).getBlockAttributes,
	blockClientId,
	richTextIdentifier
	),
	};

It might be something that should be addressed upstream (WordPress/gutenberg#23428). I haven't yet found a way to work around it. I thought maybe we could remember the select('core/block-editor').isCaretWithinFormattedText() value and restore it with dispatch('core/block-editor').enterFormattedText(), but that wasn't sufficient.

https://github.com/WordPress/gutenberg/blob/trunk/packages/block-editor/src/components/rich-text/use-caret-in-format.js