Login page with presupplied domain name?

Login page with presupplied domain name?

Is it possible to provide the login page a domain name as part of the URL, in order to be able to login with just a username instead of a fully qualified user@domain?

For example, going to https://www.zoho.com/mail/login.html?domain=domain.com then logging in with "user" instead of "user@domain.com".