Do characters with darkvision have disadvantage on perception in darkness?

@JeremyECrawford Do characters with darkvision have disadv on perception in darkness since it's treated as dim light & lightly obscured?

— Todd Lyman (@TreeofSilver) May 17, 2017

If something is dim light, it follows the rules for dim light (PH, 183). This is even true of the dim light in the rule for darkvision. #DnD https://t.co/ituPIpRZvd

— Jeremy Crawford (@JeremyECrawford) May 17, 2017