In 1988, the UK's passport changed from a dark blue colour to a burgundy one as part of our membership of the EU.
Now there are calls for the dark blue colour to be reintroduced as part of the UK's plans to leave the European Union after the June referendum vote.
The above map, created by Wikipedia user Twofortnights, is accurate for the passport colours of world countries as of 14 May 2016.
While some people are mocking the fact that anyone is even talking about this seriously, or that anybody actually cares...
...others are pointing out that some people may have voted in the referendum over this one issue.
Which is like choosing what colour to paint the house before you incinerate it...
More: The passport map of London is beautiful
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