I am on 10.14 because there are some 32-bit apps I can't replace (either because there are no 64-bit versions, for instance some old emulators, or because there are but they cost money, or there are but they have other changes which I don't like. MS Office is an example of both of the latter.

It does work, but it's a little clunky IMHO. For instance, if you press Return in the middle of a line, I expect it to split the current paragraph into 2, but not in OutlineEdit (or Outlinely or OmniOutline).