I have an xml rule I would like to add, which whitelists words which are abbreviated by ellipsis, as I don’t want these to be reported as spelling errors.
Is there a way to define xml rules that span multiple languages? Do I just need to define as a Java rule?
Yes, I think you’d need to add a Java rule, and even then, it only becomes active once it’s referenced in each <Language>.java file in getRelevantRules().
There is a file named disambiguation-global.xml
The rules in this file are used by all languages (or at least all languages with this option enabled).