How can I make a rigidbody box slide instead of roll when I push it?

I want the box to slide along the floor when I push it, but it seems to catch on it’s front corner and roll over very easily. How can I prevent that? The terrain is uneven so I can’t just lock it’s rotation.

You could also put a script on the Cube that “locks” its rotation to the normal of the ground every Update(), which you can find by Raycasting.