Hi,
As part of concluding SUL finalization, users who do not have a global SUL account will no longer be able to login. They will receive an error message indicating that their password is invalid.
This should affect practically nobody. There are a few unattached accounts left (e.g. T98156) but those shouldn't cause issues.
If a user is complaining that they are unable to login, you can check [[Special:CentralAuth/$username]] to see if their account is in fact unattached. If that is the case, please file a bug in the SUL-Finalization project[1] and I'll take a look. We are also logging denied logins, so I'll be checking that log over the next few days.
[1] https://phabricator.wikimedia.org/maniphest/task/create/?projects=SUL-Finali...
-- Legoktm
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