I don't know if I have something set up wrong for my character (a Champion Fighter in D&D 5E), but in my game I set the crit range for my weapon to 19, but the crit damage didn't roll when I rolled for damage. I rolled with designated disadvantage, and rolled a natural 20 and a 19. I have that result posted, as well as my configuration for the attack. If someone knows if I did something wrong, please let me know.