Hide logout menu link from anonymous.

The title says "menu link" but the problem/motivation says "path" -- and the patch changes the routing.yml, not a menu link.

Yes, the /saml/logout path is accessible to anonymous users. That has been done explicitly in #3043704: Make user logout more robust → . If someone who is already logged out from the Drupal site gets redirected from the IdP as part of a multi-site SLO flow, then that SLO should not be interrupted (the user should get redirected back to the IdP).

The menu link provided by this module works, because it switches between "log in" and "log out" according to the user's status.

I suspect you added a 'simple' menu link with path /saml/logout through the admin UI, and want it to automatically disappear when the user is logged out. Unfortunately you cannot do this by blocking access to the /saml/logout route, because of the above.

Please close or provide more info as appropriate.