It seems that I can turn the Logging-of-work feature on or off for the whole jiira instance only. Or i there a way to limit it to only certain projects without the need of an addon? as far as i can see i cannot restrict the fields to certain projects.
Each project has Work on Issues permissions in the permission scheme.
So basically it is just a matter of setting the desired permissions for Time Tracking in your permission scheme(s) should get you there:
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