Interceptors remain active

Let say an interceptor is used in a configuration file. that is fine. After dropping the related configuration, it seems that interceptors are not removed from the interceptor list. Need to test it, and if this is the situation, fix it.

Reproduce the configuration flow described in the issue: configure an interceptor, then drop the related configuration and inspect the interceptor list. Add a regression test for the removal behavior, and consider the issue done when dropped configurations no longer leave their interceptors active.

Written by the indexing model from the issue text.