This page lists some statistics for Swedish Wikipedia. The number of active users ("varav xxxx aktiva") should be around 2 600, but it seems like something happened September 11th. The number went from 2,645 to 4,108, and then continued to increase. It does not feel reasonable. Is there something wrong?
Note that it's a normal wiki page - ie. its content is updated by editors or bots, not by Mediawiki. See https://sv.wikipedia.org/w/index.php?title=Wikipedia:Statistik/Statistik&action=history.
It is now back to normal, I propose to close this issue. It can be reopened if it comes back.
Given it happened between 11th September and 9th October, it was possibly an issue which was fixed and deployed on 9th October.