In many projects (incl magnolia_main), we work around classloader issues (typically not finding bootstrap files), by setting useManifestOnlyJar to false. Setting useSystemClassLoader to false seems to be a more recent and better way to achieve the same. It seems that many of our projects require this workaround, and few, if any, will be hurt by it.
See https://maven.apache.org/surefire/maven-surefire-plugin/examples/class-loading.html for details