losefullscreen - bakkeby/patches GitHub Wiki
By default in dwm it is possible to make an application fullscreen, then use the focusstack keybindings to focus on other windows beneath the current window (or open a new terminal behind the scenes).
This can leave you in a situation where it is not obvious how to get back to the fullscreen window up front in order to exit fullscreen.
There exists a patch alwaysfullscreen that aims to avoid this by disallowing another client to be focused while a fullscreen window exists.
This patch ensures that clients lose fullscreen if they lose focus.