Which country's food label rules surprised you the most?

I build labelling software, so I have read more food regulations than is healthy. Three that caught me off guard:

Mexico puts black octagonal warning seals on the front of the pack (excess sugar, excess sodium, and so on). A product can need four of them at once.

The UK traffic-light scheme colours fat, saturates, sugars and salt per 100g, but the thresholds for drinks are different from solids, so the same recipe can be amber as a sauce and red as a drink.

Canada requires every mandatory element in both English and French, and the bilingual Nutrition Facts table has its own layout rules, not just translated text.

If you sell a physical product across borders, what rule made you stop and say "wait, really?"