Triple Massey products in Galois cohomology

Fix an arbitrary prime $p$. Let $F$ be a field, containing a primitive $p$-th root of unity, with absolute Galois group $G_F$. The triple Massey product (in the mod-$p$ Galois cohomology) is a partially defined, multi-valued function $\langle \cdot,\cdot,\cdot \rangle: H^1(G_F)^3\rightarrow H^2(G_F).$ In this work we prove a conjecture made in [11] stating that any defined triple Massey product contains zero. As a result the pro-$p$ groups appearing in [11] are excluded from being absolute Galois groups of fields $F$ as above.