Minifying windmills do not update their required clear area.

[HxxxxxS]

I moved a windmill, and then built a structure where it used to be. Now the windmill says "blocked by slate wall" despite being in the middle of an open field.

[HxxxxxS]

This also allows me to move a windmill up against a wall and still get full effect from it. I can move them into the mountain and get infinite wind power.