It is true that Roma are so strong when playing at home, if we take a quick look at Roma's statistics in the last 10 matches at home in all competitions, they have managed to get 6 wins, 3 defeats and 1 draw. Actually, this result is quite good considering that they are very superior when playing at home and the support from Romanisti will always be with their favorite team in the match against Salzburg in the second leg later. Even though it sounds difficult, I think Roma will still win and I don't rule out the match going to extra time.
Rb Salzburg is very strong enough this season even in the domestic league they have only lost 1 time in the 18 matches that have been played. I see a stronger chance that Rb Salzburg will advance to the round of 16.