I just recently downloaded XCode9 Beta6 and have been running through some Metal tutorials from Apple.
I've noticed that I cannot edit the Markdown files, only view them as Markdown. From what I've read, it should be possible to edit the files. I can click and highlight text, but when i try to edit it I get the bell. It doesn't seem to go into 'editing mode' ... I've tried various other ways to edit the file in XCode and only managed to do so in an external editor.
Did I misunderstand the feature, missing some workflow, or is this a bug?