Hello @Amrutha Raphael , thank you for reaching out. There is no way to fetch the access-token from any application that uses MSAL/ADAL as the library, be it a first-party app like office365 apps or any other third party applications. These libraries used something called an application cache and refresh token is stored in the application cache so that it can be used later on for fetching new accessing tokens and maintain the session.
One of the other things that can be done is utilizing the PRT (Primary Refresh Token) which is used by all first-party apps to maintain the SSO. Not sure totally if you can use that with third-party apps or not. You can read more on PRTs here: https://learn.microsoft.com/en-us/azure/active-directory/devices/concept-primary-refresh-token
But as far as the access-token is concerned, you would have to fetch an access-token for each individual app as that's what we recommend. You can use the OAuth 2.0 flows and fetch an access-token from AAD using the preferred OAuth 2.0 flow.
I would suggest, add independent authentication with AAD using the recommended library i.e MSAL and fetch the access-tokens from AAD. That way things would be cleaner and more secure. You can refer to the following doc to check on the different samples available in various programming languages and all implement OIDC to get the users authenticated to AAD and then use MSAL to fetch the Access-tokens from AAD.: https://learn.microsoft.com/en-us/azure/active-directory/develop/sample-v2-code
Hope this helps.
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