Display assemblies for supporting displays on stands or support arms have mount portions to removably attach to the displays using magnetic assemblies and latches. The magnetic assemblies and latches can improve user experience and allow the display to be installed on a support arm from the viewing side of the display and without having to see or reach behind the display. Magnetic structures can center a mount portion of the support arm and a recess of the display and can attract them to each other. Laterally-extending latches can ensure the display is not inadvertently removed. Locking mechanisms can prevent the display from being rotated to a portrait orientation when sufficient space around the display and the necessary user intent is not provided.