Group colour (icon), how is it working?

[Siedlerchr (Christoph)]

JabRef uses an external library which uses an older version (v1.7.22 of Material Design Icons)

Here is a list of Icons that should be usable in JabRef:

https://gist.github.com/Siedlerchr/69119a00d93c8fbe7b31a1d828f0588e