Hello @Roshan Jha , I apologize for the delay in my response. I did check and would like to confirm that Azure AD will require HTTP POST for token submission during sign-in. HTTP-redirect isn't supported. Note that the recommended is WS-Fed for 3rd party IdPs connecting to O365.
You can read more on this here: https://learn.microsoft.com/en-us/azure/active-directory/hybrid/how-to-connect-fed-saml-idp#supported-bindings
Hope this helps.
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