The hot spots conjecture for mixed eigenfunctions in triangles

Let $T$ be a triangle with mixed boundary conditions: Neumann conditions on two sides and a Dirichlet condition on the remaining side. Consider the first positive non-trivial eigenfunction of the corresponding mixed Laplacian problem. Hot spots conjecture for mixed triangles. Its maximum occurs at the corner opposite to the Dirichlet side. This question is part of the 2012 Polymath project on the hot spots conjecture. The surrounding linear problem has since seen substantial progress, but the source presents this specific mixed-boundary question without stating a resolution.