Improving cashing
I just now (16.11.24) realized that when I bot-created every entry for Category:Manuscripts by library but, only that old one for Admont was shown to logged-out users. The same problem (seemingly different numbers of entries depending on logged-in vs. logged-out) occurred with Category:Manuscript in Admont, Stiftsbibliothek, and the link from Albi, BM to the corresponding category appeared red only when logged out.
I solved the problem for those pages after some googling and performing a purge on the affected pages like suggested here.
But of course I have no idea if the same problem exists for other pages as well, and the solution can't be to manually check over 400 pages (even though all of the affected pages were older than the edits of today and a few random samples seemed fine).
Additionally, it might be possible for the same problem to occur again under different circumstances seeing as I'm not sure what exactly caused the cache to not reload. And it was pure chance I noticed, I don't think this error is easy to stumble upon under most circumstances.
On the other hand, maybe this is very unlikely to happen again, and after some time the cache will reload anyways, so it might not be worth fixing. But it's probably at least worth to think about.