Topic on Talk:Left 4 Dead 2
As part of The Last Stand update, Valve actually went ahead and updated Left 4 Dead 2's General Controller Support via Steam Input (some of which isn't covered in the patch note), such as:
Native Support for Standard Controllers (DualShock 4, Xbox One Controller & Nintendo Switch Pro Controller)*, Steam Controller Config Layout is overhauled to be closer to XB360 counterpart, Joystick-like Camera (for Standard Controllers only), Gyro Aiming enabled by Default for Controllers with Motion Sensors, New Game Actions, Improved Menu Navigations/UI and fixes.
- however, Steam Controller and Keyboard/Mouse Button Icon/Text is still there.