It may be called a "cropped delta" but that is not the actual genesis of this design. The very shallow chord at the point of the wingtip is producing very little lift. "Cropped" makes it sound like they started with a 40 foot wingspan design and just cut two feet off each wingtip creating a 36 foot cropped delta. (Image on left)
But you can look at that from a different perspective. That same picture could be an aircraft designed to have a 36 foot wingspan, but the chord length of the wings were lengthened (creating a deeper wing front-to back) to maximize lift. (Image on right)
In other words your picture is not a 40 foot delta with the wing tips clipped, it's a 36 foot delta with a few feet of additional chord added to the wing.
It doesn't prevent stalling, rather it delays stalling and improves roll control in a stall. In the picture I posted, the yellow aileron/elevon on the left is exposed to the turbulent flow behind a tiny wing chord. On the right, the yellow aileron/elevon doesn't start experiencing turbulent flow nearly as early.