My tmux session for a given project typically has two horizontal tmux panes with Vim occupying the top 80% of the screen and a shell running below that occupying the remainder. For the most part I stay in Vim, splitting often, and moving amongst those splits with ease. Then I’ll decide to pop down to the shell split for a moment and confidently hit <C-j>… nothing. Hmph. Let’s try again. <C-j>… not