Using SSO to sign up for an account bypasses some of the information that needs to be filled out

[matrixbot]

This issue has been migrated from #16256.

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Description

For example, assuming that the server is set up to require an email address to register in order to avoid spam as much as possible, when I use GitHub OAuth for authorization to sign up for an account, I can sign up for an account without filling in my email address.

Steps to reproduce

• Set Synapse to have to verify email address to register
• Setting up to allow third-party authorization registration, such as GitHub OAuth
• Sign up for an account using GitHub OAuth without verifying your email address

Homeserver

Matrix.org can reproduce this situation

Synapse Version

Synapse 1.91.1

Installation Method

Debian packages from packages.matrix.org

Database

IDK

Workers

I don't know

Platform

Matrix.org

Configuration

IDK

Relevant log output

IDK

Anything else that would be useful to know?

No response