Nothing is returned for categories. This is a new issue, separate from the well-known caching issues in other CategoryTree bugs.
Nothing is returned whether you're logged in or out.
This page is supposed to have multiple pages listed under _each_ of the sections in it. It is currently reproducibly empty for everyone.
https://meta.wikimedia.org/wiki/Grants:PEG/Index/Requests
Version: unspecified
Severity: blocker
See Also:
https://bugzilla.wikimedia.org/show_bug.cgi?id=61097
https://bugzilla.wikimedia.org/show_bug.cgi?id=62325