My contract with a German company, specifically had clauses saying that anything on their systems is something that can inspect and/or look at.
We aren't talking a small company here, but one with multiple large sites; which means multiple large workers councils ( basically a union for a specific company location ).
Remember hiring in Germany has to be approved by a Worker's Council and the company has to pay for the council to receive independent legal advice as well.
From the GDPR training I did for working as a software engineer in DE, this is all OK as long as its legitimately required for compliance, explicitly disclosed to the full requirements of BDSG/GDPR and not used for anything other than the stated reasons.
This is a huge contrast to the US where it would likely be completely legal to look at this kind of monitoring and then fire someone under at-will employment law for reading too much news.ycombinator.
https://www.hldataprotection.com/2017/08/articles/internatio...
GDPR also applies to the employer and employee. You can’t log without consent, and „we might monitor stuff“ in your contract won’t hold up in court in Europe if you start invasively logging.