Lock page navigation layout

When a document is locked, editors are able to reorganize pages in the the left panel that shows all pages in a doc.

We have users that often accidentally drag the pages, moving them out of a subpage into another parent’s subpages, or other similar problems.

The page locking feature should by default lock the doc page layout. I don’t even see a need to make it editable without unlocking, but it wouldn’t hurt to add an option to enable that.