Several react apps at the same page causing error unable to find an active editor state

The problem occur when several react apps with editors are used at the same page.

The first react app that is getting focus works as expected no matter which app it is, but as soon as another app is getting focus an error occur that lexical is unable to find an active editor state. The first app editor is still working as excepted (sometimes).

Lexical version: 0.12.2

```
Uncaught Error: Unable to find an active editor state. State helpers or node methods can only be used synchronously during the callback of editor.update() or editorState.read().
at getActiveEditorState (Lexical.dev.js:7379:1)
at $getNodeByKey (Lexical.dev.js:721:1)
at ParagraphNode.getLatest (Lexical.dev.js:4090:1)
at ParagraphNode.getParent (Lexical.dev.js:3690:1)
at ParagraphNode.getIndexWithinParent (Lexical.dev.js:3664:1)
at internalResolveSelectionPoint (Lexical.dev.js:6682:1)
at internalResolveSelectionPoints (Lexical.dev.js:6787:1)
at internalCreateRangeSelection (Lexical.dev.js:6898:1)
at internalCreateSelection (Lexical.dev.js:6851:1)
at beginUpdate (Lexical.dev.js:8008:1)
```
Not sure if this is a bug? I have tried to use unique lexical namespaces for the apps, but it doesn't make any sense.

Start by reproducing the issue with several React apps containing editors, using the reported Lexical version 0.12.2. Trace the reported stack from beginUpdate through internalCreateSelection and getActiveEditorState in Lexical.dev.js, then compare behavior when focus moves between editors. Done means the editors can change focus without the active editor state error.

Written by the indexing model from the issue text.