This is implemented in the next release. Note that this has some side effects.
If a user does not have permission to view the page's list of categories:
- They cannot see the category box at the bottom of the page either.
- They cannot edit a page's categories after the page has been created, even if they have permission to add the page to categories.
A similar permission has also been added to handle "Feeds that show this page", which also affects the feed box at the bottom of the page.