It was a clear penalty, Dias should not have grabbed him, the second you do that it's a foul anywhere on the pitch, the box is no different.
However, I dislike how it always has to be either a penalty or a dive, it can be both and often is.
Salah should have been awarded the penalty but also booked for diving it was pathetic and I'm sick of pundits using the "its part of the game" or "there's contact" lines to excuse it. Needs stamping out of the game and the only way that happens is if refs start punishing it and also awarding penalties for fouls when a player tries to stay on his feet which is a big part of it.