Code available on GitHub https://github.com/daattali/oldschool-github-extension

Features

1. Move header tabs to main content area: In the June update, GitHub moved the header buttons ("Code"/"Issues"/"Pull Requests"/etc) to the far left of the page. This became an issue if you have a big wide monitor because those buttons are now very very far from the rest of the page content. If you're on a laptop you probably won't notice the difference.

2. Highlight selected page in header: Prior to the update, the selected page you're on was clearly highlighted. The update made the current page selection much more subtle.

3. Classic-syle buttons and labels: The old buttons had depth and bold font, and the new buttons are flat and look less clickable.

4. Add row separators in file explorer: The file explorer that shows all the files and folders currently has no borders between rows, making it harder to read the file list.

5. Remove circular user images and rounded corners everywhere: The new circular user photos result in unwanted rounding near the corners, cropping significant features from photos that are intended to be square for some users. Many other items were also made very round.