It's Ramadan. What do Muslims at extreme latitudes do?

Right now, there are parts of the world where the sun does not set, or does not rise. How do Muslims in those regions observe Ramadan?

(Yeah, I know, I could probably get the answer from Google, but I figured if there’s any place where I could get a straight answer, it’s here.)

I can offer a previous thread on this subject.

TYVM!

I do know that people are exempt from fasting if doing so will endanger their health.

… freeze?

A relative of mine, who lives in a Scandinavian country, converted to Islam a few years back. During Ramadan, he follows Meccan time rather than local time, i.e. regarding sunrise and sunset. He told me this practice is considered perfectly A-OK by some major theologian at Cairo’s Al-Azhar University, which he (along with most of the Sunni world) considers a trustworthy authority.