How could we specify the organization url param, without knowing who the user are? The whole point of using auth0 is that auth0 takes care of the authentication of the user.
If I understand the suggested solution we need somehow find out who the user is, without using auth0, in order to present the possible organizations and then login them via the universal login?
Normally the user logs in, gets the organizer picker, and everything is handled by auth0.
For your use case, you may want to ask the user to specify the Organization name before providing their credentials (this being an option in the organization settings), or you could look at listing the organizations in your application by using the management API as per the suggestion here - Support more than 20 organizations in Organization Picker - #4 by adam.housman
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