Zhang–Liu–Wang conjecture on the adjacent vertex distinguishing chromatic index

Let $G$ be a finite simple graph with no isolated vertices. Write $V(G)$ and $E(G)$ for its vertex and edge sets, let $\Delta(G)$ be its maximum degree, and let $\chi'_{a}(G)$ denote the smallest number of colors in an adjacent vertex distinguishing edge coloring of $G$. A graph is normal if it contains no isolated edges. Zhang–Liu–Wang's conjecture. If $G$ is a connected normal graph different from a $5$-cycle and satisfies $|V(G)|\geqslant 3$, then

$$\chi'_{a}(G)\leqslant\Delta(G)+2.$$

The conjecture concerns an upper bound for the adjacent vertex distinguishing chromatic index in terms of maximum degree. The supplied source does not state whether the conjecture has been resolved.