Tmux will exit right away if reattach-to-user-namespace isn't installed. Seems like we probably shouldn't have it in our dotfiles if not everyone is going to install it
Can we hook into this somehow to detect whether it's installed and recommend the user install it before exiting? Tmux is still usable without it but not running it is going to be more confusing when tools like open, launchctl, and other binaries don't work properly.
Would a function for reattach-to-user-namespace that:
... do the trick?
This was done in d830652