All reports of unknown-java-class-version for the archive. The extended description of this tag is:
The package contains a Jar file with Java class files compiled for an unknown Java version. Most likely the class file is corrupt or compiled for a newer version of Java than Lintian knows about. In the latter case, please file a bug against Lintian.
The latest class version known by Lintian is Java11 (Major version 55).
Severity: normal, Certainty: certain
Check: java, Type: binary, source
This tag has not been emitted in any package tested by Lintian.