The test perfschema.nesting is failing with a result difference if the server has been built cmake -DWITH_WSREP=OFF. These differences seem to be specific to MariaDB 10.4 and later. In 10.3, the result is unaffected by WSREP changes.
One difference seems to be that WITH_WSREP=ON is causing extra operations on LOCK_thd_mutex.
Note: The test is disabled on Windows. We do not seem to have a builder that repeats the problem on 10.4. On 10.5, the builder 32bit-ubuntu-1804 is constantly failing due to this bug.