Navbar barrierearm

components/Navbar/NavbarSubMenu.tsx

@@ -71,6 +71,7 @@ export const NavbarSubMenu: FC<Props> = ({
       <ul
         ref={subMenuRef}
         id={`submenu-${id}`}
+        hidden={!open}
         className={[
           styles["nav-submenu"],
           open ? styles.open : "",