I believe that’s known and intentional - we try to minimize the
customizations to templates because applying customizations slows down
and adds complexity to applying security updates.
The template, as I recall, has to be customized to use our login. The
same issue holds true for the mobile template.
Pre-login, use the openSUSE-CMS style - after login, switch to the “Basic
Green” style if you like. Or set the “Basic Green” style as your default
in your user settings, and use the CMS style pre-login.