Here's what they said:
1. "If you're in Argentina and say to someone, 'The Falklands are British, and Maradona wasn't that good.'"
3. "Never point the bottom of your shoe to a Middle Eastern Muslim. It's considered disrespect, since the shoe touches the ground."
4. "Once innocently assumed a Welsh dude to be English based off his name. He did not like it."
5. "I remember telling a Canadian from Toronto that their accent isn't that different from the States. We have Timmies on the West Coast too. For some reason, they fucking lost it. Like Ontario is basic Canada — it's just a fact of population."
6. "When people ask every Asian person if they are from China."
8. "'Basque Country'? Oh, that's part of Spain, isn't it? It's an autonomous community in northern Spain."
12. "Claim that the EU is a single country like the US. That, historically for me, has really ticked off Europeans. Also, refer to someone from Europe as a European. They really want their individual area to be acknowledged."
13. "Never refer to the Liancourt Rocks as 'Takeshima' instead of 'Dokdo' to a Korean person's face. That's the quickest way to get them to hate you."
14. "A lot of Americans get offended when you hang an American flag the wrong way."
Did they miss any? Let me know in the comments below!
Responses edited for length/clarity.