Did a search, but couldn't really find anything on this. Wondered if anyone has had the same issue and if so, how they solved it?

Scenario. Today I was on the MTB in the forest backblocks. I carry a Garmin inReach Mini and use this for comms, preferably paired with the phone. After the sun had gone down (dry weather) the temperature dropped to around 3C, and I needed to arrange a pickup. The phone was impossible to use and full of misskeys (like way WAY out) and pretty unresponsive to swipes. I did not notice at first, but discovered the screen had an almost invisible film (not droplets) across the entire screen. Condensation because of the cold temps and humid forest. Almost impossible to wipe dry as it would form almost immediately again. Keeping the phone warmer, like on the body, could be an option, but I don't do this as it tends to get covered in, well, sweat. And in turn, that can cause other problems.

I'm not sure if it matters, but the phone is a OnePlus 5, still with it's factory screen protector on.