It's not what you're looking for, but it might be interesting to note that there's a pretty capable window manager (hybrid tiling/floating) that runs in Emacs,

It's not what you're looking for, but it might be interesting to note that there's a pretty capable window manager (hybrid tiling/floating) that runs in Emacs, written in Emacs Lisp, and indeed lets you jump between windows using your buffer switcher. https://github.com/ch11ng/exwm https://github.com/ch11ng/exwm In the tiling mode, Emacs buffers and X11 windows map 1:1. It's like having arbitrary X programs inside Emacs.