YSK to never be in the sun with citrus juice on your skin (such as after making backyard margaritas) because the juice will make your skin hypersensitive to severe sunburns in a reaction called margarita photodermatitis

This happened to my neighbor last weekend, he was having a pool party making margaritas for the adults and he got citrus juice all over his hands and didn't wash them before coming outside. Within just a few minutes, he said his hands started to really hurt. Within an hour, they were red and raw. His wife ended up having to take him to the ER and he came back with small blisters all over his hands (which turned into larger blisters over a few days) and the doctors diagnosed it as margarita photodermatitis.

This is one of those things I had NO clue about that even existed and I hope that this could spare a redditor from some very painful burns.