MFA for guests users
I setup a policy on conditional access in my azure portal to enable MFA for guests users, but it only works for MS teams, i tried for example in azure devops and it doesn´t asks for it. In the selected apps i have office 365, ms teams, Azure devops and Microsoft Azure management.
You can check the sign-in logs in AzureAD to do some checking if the authentication to Azure DevOps was maybe still done using MFA - e.g. when using certain browser the users access token might also include a MFA claim; https://docs.microsoft.com/en-us/azure/active-directory/reports-monitoring/concept-sign-ins This would be the most probable reason why no MFA prompt was seen.
Also worth readin gin this regard: https://docs.microsoft.com/en-us/azure/devops/organizations/accounts/change-application-access-policies?view=azure-devops&tabs=preview-page
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