Private Webster is an American G.I. who makes a one-time appearance in the Season 7 episode of M*A*S*H titled "Commander Pierce". The part of Private Webster was played by James Lough, who also played several other G.I. characters, notably PFC Felix Kornhaus.
About Webster[]
Webster's rank is not mentioned in the episode. His rank is inferred from his relative youth and the fact that credit listings sometimes (but not always) leave out the rank for Privates but specifically mention the rank in the case of Corporals and Sergeants. The credits for the same episode also list a Corporal Hough for example.
Webster has a brief scene in post-op in the early part of the episode. Hawkeye is examining him and tells him it is time to remove his drainage tube. Webster is terrified and asks if he can have something for the pain. Hawkeye however tries the doctor's trick by continuing to talk to him and distracting him while doing the procedure so that by the time the conversation is over, he has already removed the tube without Webster even noticing it.