[NTG-context] registers in footnotes as page glossaries

Hans, I wonder whether MkXL may have page registers for footnotes. This would be great to have page glossaries, such as in https://geoffreysteadman.com/wp-content/uploads/2017/08/lysiascrito-24aug17w... (first apparatus). To be fair, I have asked that a while ago (with MkIV). It would be great to have these page glossaries as language aids. Right now, they need to be composed manually (using a word processor, no TeX). Many thanks for your help, Pablo