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A feature included with the Password flow is the ability to present additional login options to the user and call them directly as subflows in response to some form of user input or client-side script. This is useful if you want most users to have the option to use a password, but make more advanced options available at the same time without requiring extra pages or clicks to reach the password option.A key advantage is that it allows error handling in response to other login flows to be handled by the username/password login view, to avoid stranding the user or having to return an error for the overall request. The second advantage is that allows the Password flow and the extended flow(s) to be combined without prior knowledge of each other
This feature has been superseded by the MFA login flow implemented in V3.3 and is much more flexible and usually simpler to use, even though it's more complex to understand at first. There are no explicit plans to deprecate or remove this feature yet, but migrating away from it would be a good decision.
Basic Setup
Some preconditions for using this feature:
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