ayi What you are trying to do is completely wrong - why to reverse-engineer frontend app and one day to find that everything changed? There is official REST API to ms outlook online and authentication mechanism via Azure AD - exactly to let third-party apps to work with MS online apps. Try to checkout this: https://learn.microsoft.com/en-us/graph/overview-major-services and this: https://learn.microsoft.com/en-us/graph/azuread-identity-access-management-concept-overview
