If someone attacks someone else while both are in darkness or a fog cloud is it at advantage, disadvantage, or cancelled out? The RAW people have it. You would be justified forcing some means of knowing what space the target is in, unless quick combat is the goal.

— Chris Sims (@ChrisSSims) October 28, 2017

Fictional media often depicts such a situation has two foes flailing around each other.

— Chris Sims (@ChrisSSims) October 28, 2017

Incidentally, that was why miss chance was part of 3e. I'm not sure it made the game that much better though.

— Chris Sims (@ChrisSSims) October 28, 2017