Possibly, but that's a lot fancier and less "just works" than I'm interested in. I just want the same extremely simple "what words have I seen before" autocompl

Possibly, but that's a lot fancier and less "just works" than I'm interested in. I just want the same extremely simple "what words have I seen before" autocompletion that you get on a file-by-file basis, but as if I had every open file concatenated into one.