I have tried over and over to get snapping faces to work. Occasionally it works and I have no idea why. But it seems the main problem is that it always wants to snap to the MIDDLE of an object. Even if I try and move the 3D cursor to the bottom.
I have set the snapping to face, active, align to rotation and snap to individual elements. I am using the control key to snap.
As you can see in the screen recording, when I snap, the cylinder pops into the middle of the box, which is no good. Nothing I seem to do helps. I also wonder if there is a way to snap faces while in edit mode, which would be super helpful.