Checkmk offers a method to authenticate single web requests with URL parameters (_username and _secret).
Due to some refactoring of the session handling with Checkmk 2.2 such automation requests initiated a full session.
The login for automation users was still blocked in the login screen but an authenticated request initiated a full session that could than be used to browse the Checkmk GUI like a regular user.
With this Werk that is no longer the case.
If you use this authentication method you should check if you rely on sessions for your automation users.
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