Grey forest tile in map view

First post. Why is a single forest tile near me grey and not green. I explored it and didnt find anything unusual there.
It only turned grey recently, as well.

Fungus? I really don’t know.

Maybe there’s a Fungal Bloom near that :slight_smile: or…i don’t know xD

maybe you marked it explored . marking turns tiles grey.

This.

I think there should be a way to automatically mark explored as you go! And to be able to mark other tipe of stuff without using notes. I’d love to mark things for strategies

I must have accidentally hit the hotkey at some point.
Thanks.