Question: did the actor who played mark on roseann die

Answer: Yes, Glenn Martin Christopher Francis Quinn (May 28, 1970 -- December 3, 2002) was an Irish actor. While he was best known for his portrayal of Mark Healy on the popular '90s family sitcom Roseanne, Quinn also amassed a large fan base for his portrayal of Doyle, a half-demon, on Angel, a spin-off series of Buffy the Vampire Slayer.