The browser might overrule it anyway, if it's really obvious that it should be cached.
This is mainly so Cloudflare, etc. don't serve sensitive documents to guests.
The topic list should only be rebuilt for a short window after something related to it changes on single server setups.
Swapped out the RebuildGroupPermissions call in UpdatePerms with a more general and versable Groups.Reload call.
The template generator now use log instead of fmt for writing debug logs.