This isn't [only] two panes, but it gives you the ability to navigate files while still seeing the directory structure: https://github.com/sr3d/GithubFinder htt

This isn't [only] two panes, but it gives you the ability to navigate files while still seeing the directory structure: https://github.com/sr3d/GithubFinder https://github.com/sr3d/GithubFinder It's implemented as a bookmarklet that you can activate on any github repo for an advanced view.