Lie-operad conjecture for natural operations on Lie cohomology

Let ${\mathcal L{\it ie}}$ be the Lie operad, and let ${\mathcal B}_{{\mathcal L{\it ie}}}$ be the operad of natural operations on the cohomology of Lie algebras. Lie-operad conjecture. The operad ${\mathcal B}_{{\mathcal L{\it ie}}}$ has the homotopy type of the operad ${\mathcal L{\it ie}}$. This is one of the paper's conjectures about the homotopy type of the operad of natural operations; no proof or resolution is supplied in the given text.