Horizontal Window Resizing

[thenickygee]

Opening a new discussion from comment on #1324:

Request from @joshstobbs: "is there a way to resize left and right with my keyboard? I basically am looking to emulate dragging the side of the app but by pressing a hotkey instead."

EDIT: I see now from #1599 we can do it by adding the shortcut via the CLI. I am guessing this shortcut isn't in the setting UI due to this statement in the terminal commands: "The preferences window is purposefully slim..."