This looks great, I think it solves an existing need and could be extended beyond editing files on GitHub, to be a more general-purpose tool.
One suggestion: a demo where a potential user can try editing files without needing to authenticate with a GitHub account. I actually haven't seen the editing interface yet - I'll clone the repo locally since I'm curious, but it would be a better on-boarding process if I could try it first.
The access token will work out of the box (it is hardcoded), and the site is a Jekyll which will automatically be rendered by GitHub and shown at https://geraldoquagliato.github.io/
One suggestion: a demo where a potential user can try editing files without needing to authenticate with a GitHub account. I actually haven't seen the editing interface yet - I'll clone the repo locally since I'm curious, but it would be a better on-boarding process if I could try it first.