What is the first movie remake of another original movie (wholly written for the screen, not based on a book or play)?
Intermezzo (1936) seems to have an original screenplay co-written by director Gustaf Molander which was remade in 1939 as a David O. Selznick production. This is the one to beat, I guess. (I was thinking The Man Who Knew Too Much, 1934, 1956, until I remembered this one.)
I'm not looking for shorts, like Our Gang or the like, but a feature. I don't want to get too bogged-down by run-times, just use your best judgement here as to what constitutes feature-length. (Even back in 1936, Intermezzo was 93 minutes long. Don't pick something too short, okay?)