> go to GitHub and navigate through the file tree. On my machine, this feels significantly snappier than the the rest of GitHub. Coincidentally, it's also one of the only parts that is not rendered statically

And it's also the only part of it that doesn't work on slow connections.

I've had a slow internet connection for the past week, and GitHub file tree literally doesn't work if you click on it on the website, because it tries to load it through some scripts and fails.

However, if, instead of clicking on a file, I copy it's url and paste it into the browser url bar, it loads properly.