Problem/Motivation
It is not currently possible to create a Page Layout Display for admin pages as /admin*.
Because we stop page layout to load in PageVariantSubscriber.php.
Proposed resolution
If we remove this line, this will create a problem on loading the admin theme for the admin page if the user as permission 'access administration theme'. Because then we don't load the admin theme and the frontend theme is missing.
This is probably a complex problem, and as a starter we should probably only support admin page layout for user that can not access the backend theme.
Remaining tasks
User interface changes
API changes
Data model changes
Comments