The third screenshot above shows that the new words end up below all the existing ones (so that they don't get in the way, especially since they're unlikely to be applicable to all file types at the same time). The above is the result of a tutorial I wrote sometime ago, but that hasn't been updated to 6.0 yet. However, aside from its value as a tutorial sample, I think it could also be useful to users in general, i.e., those who don't want to build the whole plugin from scratch via a tutorial. Hope it proves useful. It could be expanded in various ways.