Reading's separation conjecture for cluster variables

Let $\mathcal A$ be a cluster algebra. For cluster variables $u=x_{i;t}$ and $u'=x_{j;t'}$, write $g_{k;u}^s$ and $g_{k;u'}^s$ for the $k$th components of their $g$-vectors at a vertex $s$ of the exchange tree. The variables are sign-coherent when

$$g_{k;u}^s g_{k;u'}^s\geq 0$$

for every vertex $s$ and every $k\in[1,n]$.

Reading's separation conjecture. The variables $u$ and $u'$ are contained in the same cluster if and only if they are sign-coherent.

This reformulates Reading's conjectured separation property for cluster variables in universal geometric cluster algebras. The supplied text does not state whether the conjecture has been resolved.