Can't add brisk menu to mate-panel

[aaaaadrien]

Hi, On gentoo, i compile brisk-menu with standard tools (ninja-utils and meson) Compilation : OK, no errors.

When i add on mate-panel, I have an error (in french : Le tableau de bord a rencontré un problème au chargement de « BriskMenuFactory::BriskMenu »

All others extensions of MATE works.

[aaaaadrien]

DEPEND=">=mate-base/mate-desktop-1.16 >=mate-base/mate-panel-1.16 >=x11-libs/gtk+-3.18 dev-util/ninja >=dev-util/meson-0.40.0"

My ebuild : https://github.com/aaaaadrien/adrien-overlay/blob/master/mate-extra/brisk-menu/brisk-menu-0.5.0.ebuild

No instructions for compilation, so it uses default actions :

meson --buildtype plain build --prefix=/usr
ninja -C build
ninja -C build install