I noticed recently while playing MP2 in Dolphin that there is a glow along the right and bottom of the screen when using MSAA or SMAA on either OpenGL or DX11.
Without AA enabled: https://i.imgur.com/ZNeU5xX.jpg
With AA enabled: https://i.imgur.com/LzO2VOP.jpg
Without AA enabled: https://i.imgur.com/ZNeU5xX.jpg
With AA enabled: https://i.imgur.com/LzO2VOP.jpg