Do you know if I can find JabRef Class diagram anywhere? Thanks in advance!!
we have an old one only for groups (see devdocs). Back in a while you could browse the class diagrams with sourcespy For new contributors: package/class/activity diagrams - #7 by tobiasdiez
Intellij (Ultimate) can also generate uml diagrams.
Otherwise, you could try something like this (no idea if this works)