The primitive-stable domain conjecture for free-group character varieties

Let $F_n$ be the free group of rank $n$, let ${\mathcal X}(F_n)$ be its ${\operatorname{PSL}_2(\mathbb C)}$ character variety, and let ${\mathcal{PS}}(F_n)$ denote the primitive-stable locus. Primitive-stable domain conjecture. The domain of discontinuity ${\mathcal{PS}}(F_n)$ is the domain of discontinuity of $Out(F_n)$ acting on ${\mathcal X}(F_n)$. The claim concerns whether the primitive-stable locus gives the full properly discontinuous domain for the $Out(F_n)$ action; the source presents this as a conjectural implication and does not state a resolution.