Redirecting user to specifc url after firebase auth

I have web portal single page login form where on user account I want to redirect users to different URLs, for example. I have enabled email/password in firebase authentication: Now

• if user A login then redirect him abc.com
• if user B login then redirect him to xyz.com
• if user c login then redirect him to abc123.com

I mean I want to allow or restrict different domains to different users. one way is to right js code with if-else and reidrect user to a specific domain. But this is not safe as the code exists in JS.

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