“Rolling 1 or 20” for death saves saying natural 1 and 20 or modified roll?

@JeremyECrawford Is the paragraph "Rolling 1 or 20" for death saves saying natural 1 and 20 or modified roll? I think you answered this once

— Aaron Bloom (@aaronbloom15) June 4, 2016

When the rules talk about rolling a 1 or 20 on the d20, they literally mean on the d20, not after modifiers. #DnD https://t.co/yg8wE9zQ8L

— Jeremy Crawford (@JeremyECrawford) June 4, 2016

@mattdomvilleSo, death saves can be modified by bless, bane, ring of protection, etc, but special results for 1s/20s must be natural? Correct

— Jeremy Crawford (@JeremyECrawford) June 4, 2016