The conjecture for even-clique Ramsey–Turán densities

Let $R(3,s)$ be the smallest integer $N$ such that every red-blue colouring of $K_N$ contains a red $K_3$ or a blue $K_s$. Let $\varrho(K_3,K_{2s})$ denote the multicolour Ramsey–Turán density for triangle versus the even clique $K_{2s}$. Even-clique Ramsey–Turán conjecture. For all $s\geq2$,

$$\varrho(K_3,K_{2s})=\frac{1}{2}\left(1-\frac{1}{R(3,s)}\right).$$

This is proposed as the even-clique analogue of the previously recalled odd-clique conjecture. The provided text gives no resolution, so the conjecture remains open here.