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Picture this: I'm playing a kobold, who have the Sunlight Sensitivity trait (Volo's, p. 119)
You have disadvantage on attack rolls and Wisdom (Perception) checks that rely on sight when you, the target of your attack, or whatever you are trying to perceive is in direct sunlight.
Now, I assume from that wording that a normal "bright light" isn't enough - has to be direct sunlight. Except then we get something like sunbeam, which not only creates a giant mah lazor, it also creates actual sunlight. (PHB, p. 229)
For the duration, a mote of brilliant radiance shines in your hand. It sheds bright light in a 30-foot radius and dim light for an additional 30 feet. The light is sunlight.
So far so good, it sounds like standing next to (or being, come to think about it) the caster while he's doing his thing is a bad thing for my eyes.
Except now we come to the Oath of Devotion paladin's level 20 feature, Holy Nimbus (PHB, p. 86):
At 20th level, as an action, you can emanate an aura of sunlight. For 1 minute, bright light shines from you in a 30-foot radius, and dim light shines 30 feet beyond that.
Here, the light is also called sunlight, but it's in the portion of the rules generally reserved for the "fluff" of the rules - is it actally sunlight? Would it hurt my eyes? Is bear-hugging vampires a Devotion Oath paladin sport now?