Do you not realize you're in a browser, on a Web page, if you're on Github?

And do you never actually clone the project to your machine and use it? When I sit down to actually use the project and I want to read the documentation, I want to double-click on the MD files and READ them. Not edit and preview, but read... with their intended formatting.

You might have difficulty doing that without using a browser, given that markdown renders to HTML.