A cover glass element can extend to the edges of an electronic device while maintaining the optical flatness and thickness needed for the cover glass. A first glass sheet with the desired thickness and flatness can be thermally bonded to a second glass sheet machined to include an opening to be received by the edges of the electronic device. The resulting three-dimensional cover element forms a uni-body frame that is significantly stiffer than a single sheet of glass, and the larger surface area of the edge provides for enhances pressure distribution, particularly after chemical strengthening, thus enhancing the durability of the electronic device. Further, the thermal bonding process uses lower temperatures than processes such as slumping or pressing, which could potentially affect the flatness and optical clarity of the original sheet glass.