On several wikis, an account named "Abuse filter" has been created on December 17th to perform some technical maintenance on AbuseFilter. This account has sysop rights but it's a system user and no human can use it. The account already existed on wikis where AbuseFilter can perform blocks, which are issued using this account. See T212268 for more information and future plans.
In AbuseFilter, the "Throttle" action takes three parameters: count, period and groups. They must now strictly respect the requirements listed on mediawiki.org. A list of broken filters is on Phabricator. If you're familiar with AbuseFilter, please take a look and fix them.
Changes later this week
The new version of MediaWiki will be on test wikis and MediaWiki.org from 8 janeiro. It will be on non-Wikipedia wikis and some Wikipedias from 9 janeiro. It will be on all wikis from 10 janeiro (calendar).
Search Platform Office Hours is rescheduled to January 9th. Check the details for time and date.