Domain Mapping v126.96.36.199, WordPress 4.2.2 in subdir WPMS mode. Admin and login are forced to original domain, cross-domain autologin is enabled, and HTTPS is forced for login and admin pages (but not for front-end pages)
Looks like we have another bug relating to admin_url(), possibly of a similar nature to
admin_url() is returning mapped domains with https:// prefix which, in 99% of cases, will result in a CN mismatch.
In this particular instance, the problem is revealed in WPMUdev Appointments+ (v1.4.7, appointments.php lines 4158 and 5071) in which that plugin is calling wp_localize_script() with 'ajax_url' => admin_url('admin-ajax.php'). Instead of returning:
it is returning
even when admin_url() is being called with the protocol forced to http://, per this support case here:
and so the AJAX call fails because the browser won't connect to POST the AJAX request.
Let me know if there's anything I can do to assist in debugging this case.