Version 54.2 of the iOS app, released on 2017-06-27, has a new feature that allows editing of plain-text fiels with the .txt extension.
Would it be possible to expand the scope of this feature to allow editing of files with extensions of lightweight markup languages such as Markdown (.md and .markdown), AsciiDoc (.adoc and .asciidoc), and reStructuredText (.rst)? I don't mean full-blown, feature-filled editors for markup languages - it would just be useful if the current text-editing feature could be used on common plain-text filetypes that do not end in the .txt extension.