@Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException,
            IOException {
        forceBackendLogout(req);
        if (req.getSession() != null && !req.getSession().isNew()) {
            req.getSession().invalidate();
        }
        resp.sendRedirect("/apimanui"); //$NON-NLS-1$
    }
In setups where the Keycloak backend URL is different to the frontend URL, Keycloak's Java adapter currently
(incorrectly, AFAICT?) uses the frontend URL for logging out.
<p>
For example, this means it won't actually log out in situations where the internal Docker network has a different
name to the external network.
<p>
We work around this by forcing the backend URL with a delegate. It's not pretty...
manager/ui/war/src/main/java/io/apiman/manager/ui/server/kc/KeyCloakLogoutServlet.java