Summary
Can't find a page template that was recently deployed/staged?
Kentico Xperience page templates need a site association to work correctly. If a page template is not associated to a site, content editors will not be able to select that page template in the pages app when choosing the template on a document.
This situation can be caused by the Content Staging app inside Kentico Xperience not always being used correctly to sync the page template from a development environment to a production environment. Content Staging still works to create the page template in the target environment but silently misses associating the object to the target site. This check looks for any instances of this issue and reports it.