This issue only needs to be tested in 1 device. If you test this in the webapp make sure to change the User Agent, otherwise autologin won't work. In the app, login in master site with a user that hasn't used autologin in the last 6 minutes. Go to MM Dev Testing > General. Click the link "Link to Site administration (not supported in app, so opened in browser)". Check that the warning displayed before opening the browser displays the "final" link (admin/search.php). Click "OK". Check that the browser is opened and you're automatically authenticated. Now open a BBB activity that is opened. Click the Join meeting button. Check that no warning is displayed before opening the browser.