Properness of analytic stacks without unramified diagonal

The theorem concerns a morphism of $k$-analytic stacks whose diagonal is assumed to be unramified in the stated result. Properness conjecture. The theorem that this morphism is proper should remain valid without the assumption that its diagonal is unramified. This conjecture proposes removing a technical hypothesis from the properness criterion for morphisms of non-archimedean analytic stacks; the source provides no further evidence of resolution.