I assume by SaaS login you mean realm login?
Yes, that's
it.
No, there's no difference. There's is however some types of
applications where a cancel button doesn't make sense, and that's when an
application requires a login. For example the admin console redirects the user directly to
the login screen as you can't do anything unless you login. There's not much point
in that case to show a cancel button as it would just take you back to an error screen. So
the cancel button should be configurable.
That's good, since the Cancel button
in the admin console does not make sense at all.
Gabriel
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Gabriel Cardoso
GateIn Portal | User Experience Designer