my point is not so much about the markdown editor, good job to the dev for spotting a niche where he can make a product. I'm just observing that my brain (annoyingly) would have never let me create something like that.

As an aside, for my dev diary (stored on a cloud file system ) I write markdown in Vim, I used to want to see it rendered and played around with visual editors, but I like vim style editing so I just deal with it in text form with syntax highlighting and that's plenty good enough for me.