It’s not possible though because then Catagóir would be spelled wrong when used by itself. Actually, maybe even the word Category is taken from Joomla anyway so it can’t be changed.
This is a problem for all Celtic languages and any language with a case system, which is many. All Slavic languages I think.
As you say, we can only work around it, but it’s still worth pointing out that this is a very bad practice. It also reflects on JEvents down the track, as it ends up looking amateurish and unprofessional.