when you switch to gamemode 3 and spectate an enderman, you get the endeman vision (invited colors). BUT when you relog being in gamemode 3 spectating an enderman, when you log in again you are no longer spectating the enderman, but you still have the enderman vision. even if you change gamemode the endervision stays. the only way to deactivate it is by spectating an enderman again and then quit spectating.