Navigation editor: Nested block-based menu items are deleted and re-created on each save

[adamziel]

As noted in 34541:

The mapMenuItemsToBlocks function assigns the __internalEntityRecord attribute to all the blocks representing classic menu items. This way we can match blocks with menu items and update the correct ones.

Unfortunately, it doesn't assign __internalEntityRecord to nested blocks. The save function "thinks" it sees new menu items and that it doesn't see the old ones. This results in deleting and re-creating the same menu items on each save:

gutenberg/packages/edit-navigation/src/store/transform.js

Lines 174 to 184 in bf53422

	if ( menuItem.type === 'block' ) {
	const [ block ] = parse( menuItem.content.raw );
	if ( ! block ) {
	return createBlock( 'core/freeform', {
	content: menuItem.content,
	} );
	}
	return block;
	}

cc @talldan

[Mamaduka]

Closing the issue since the editor is no longer maintained and has been removed from the project.