You will need to do a few things:
1) Assign control over user.com domain to Azure (Microsoft 365).
Migrate consumer Google Workspace (formerly G Suite) mailboxes to Microsoft 365 or Office 365
2) Configure an Enterprise Application for SSO for Figma/Gitlab and all other SaaS that utilize SSO in your environment.
Tutorial: Azure Active Directory single sign-on (SSO) integration with Figma
https://learn.microsoft.com/en-us/azure/active-directory/saas-apps/figma-tutorial
3) Configure your SaaS (Figma/Gitlab) to point to Azure AD for SSO authentication.
SAML SSO with Azure Active Directory
https://help.figma.com/hc/en-us/articles/360040532413-SAML-SSO-with-Azure-Active-Directory
Once this has been completed, Figma will now look for Azure AD SSO authentication.
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