I have some groovy scripts replacing German characters like 'ß' by '.' e.g.:

directory.getName().replace('ß','.')

Now since Scriptler plugin version 3.1 when editing those scripts I see '?' instead of 'ß' and after saving the scripts they are no more working because characters are replaced by invalid characters.

I guess that files are encoded in ISO 8859-1 but now are intepreted as UTF-8.

Finally going back to Scriptler plugin version 2.9 solved the problem.