This morning's fun WordPress thing: using PublishPress to limit access to certain pages can break page rendering for the whole site (particularly around navigation elements, which is honestly where I'd expect it to happen).
Maybe the theme's relying on classes or structures that don't exist if that permission's being checked? Seems like something you'd want to avoid in theming a site.
TBC I'm strongly disinclined to blame #PublishPress for this. It is to me kind of a hot mess, but that seems to me mostly because it's trying to impose a degree of order onto WordPress that the latter's fundamentally not meant to support. (But that I absolutely need to accomplish the mission I've been assigned.)
No, feels like someone coded styles against a classname or class path that changes if you're even CHECKING Read permissions. Alas, debugging this has to go on back burner.
FeralRobots