Barnette's Hamiltonian cycle conjecture for even simple 3-polytopes

Let $P$ be an even simple $3$-polytope, meaning that every facet of $P$ has an even number of vertices. Its vertex-edge graph is the graph whose vertices and edges are those of $P$. Barnette's conjecture. The vertex-edge graph of $P$ contains a Hamiltonian cycle. This is presented as an intriguing longstanding question about planar graphs; its status is not resolved by the supplied source context.