"forbiddenRoles": "external" does not work

[MagnaFrisia90]

This is related to #15
I have now set:

                {
                "id": "Verse",
                "name": "Verse",
                "action": "add",
                "link": "https://home.solvito.de/verse",
                "icon": "https://home.solvito.de/download/logos/verse_tiny.png",
                "order": 10000,
                "new_window": true,
                "submenu": [],
                "location": "main",
		"forbiddenRoles": ["external"]
                }

But the external user can still view this link:

[MagnaFrisia90]

Any idea ? @caiaga