In a response to US President Donald Trump’s latest threat to seize control of Greenland, the leaders of the Danish autonomous region’s five main political parties issued a joint statement late Friday declaring the future of the island should be decided by Greenlanders.
A US Citizen in PR cannot vote. A US Citizen resident in a foreign country can.
This is regardless of where you are born, but in which US territory you last resided (eg proper state, Puerto Rico, etc)