Steps to reproduce

1. Login with an SSO user (not same username like existing MgnlUser in JCR by default, e.g superuser, eric) which belongs to publisher group
2. Go to pages-app and publish a page
3. Check that till you don't refresh the browser, the new task doesn't appear

Expected results

Once the public task is created, the user can see the indicator within the task app section

Actual results

The indicator that a new task exists doesn't appear till the user refresh the browser

Workaround

N/A

Development notes 

The potential root cause is LocalTaskDispatcherManager#getAllRecipients, the issue happened because the recipients (which is list of username) doesn't contain the current login user to dispatch the new task created event and update the UI (the number in TaskBadge).

More details, one of the method in SsoUserManager which is called in the method above, throws UnsupportedOperationException because getAllUsers() is not implemented for SSO.

So, we have to find another way to determine the current login SsoUser is belongs to the group ("publishers" group in this case).

One concern or limitation is we can't fire events to all users in that group in SSO cases because the users are managed by the Identity provider, I'm not sure whether we should find all users belongs to the group like Mgnl user in JCR. Open to discussion and decide later in grooming cc brenuart mrajkovic