When you open a solution, this extension automatically looks for a ReadMe file and renders and displays it in the embedded Visual Studio web browser.
This allows you to provide easy-to-find documentation for new team members, or others who are new to your project.
It supports Markdown text, meaning that it works completely transparently for GitHub projects, and has preliminary support for GitHub wiki pages.
Feel free to visit the home page. You can download it from the Visual Studio Gallery.
The source code is on github; and the wiki is here.