I must be stupid. I have a app (Firefox…) that has decided to make it’s window
slightly larger than the screen. On os x, this means the widget to resize the
window is now permantely off the screen.

So how do I resize the window without using the little thing in the
bottom right? Not having much luck finding key bindings
to do it.

Restarting the app doesnt work because it saves window size info.