The WYSIWYG editor remains read-only after it reconnects to the realtime session

Follow these steps to reproduce:

• start editing a wiki page in realtime (with the WYSIWYG editor)
• switch the browser tab or move to a different window and wait or do something else for more than 30s
• come back to the realtime WYSIWYG editor

Expected: you can continue editing
Actual: the editor is read-only