Map not displayed if Hide Hand is on

 If Hide Hand is on, maps cannot be seen.

It makes sense that tools can't be seen, as tools are just things that don't need to be seen. Maps are information, and need to be seen.

As such, I can see how this has come into the game, but I can't imagine it's intended behaviour.

 

Recreation:

Put a map in hand.

Turn Hide Hand on.

Map is no longer visible.