Shared Runitme with SSO not supported

Prerequisites

I'm implementing a word add -in that makes use of SSO , since my Add-In has to run on document load, implemented it with shared run time. Things works just fine in browser word app and team web app, but when I run it in Team desktop app, it is not able to get the access token, so it fallsback to fallbackauthdialog.js where we explicitly ask to users to login but since I'm using shared runtime the fallbackdialog.html never loads, it gives blank pop up ..

Is it possible to implement SSO and shared runtime at same time that works in teams desktop app as well?
Please answer the following questions before submitting an issue.
YOU MAY DELETE THE PREREQUISITES SECTION.

• I am running the latest version of Node and the tools
• I checked the documentation and found no answer
• I checked to make sure that this issue has not already been filed

Expected behavior

It should allow users to get access token in team desktop as well when running in shared runtime.

Current behavior

I'm implementing a word add -in that makes use of SSO , since my Add-In has to run on document load, implemented it with shared run time. Things works just fine in browser word app and team web app, but when I run it in Team desktop app, it is not able to get the access token, so it fallsback to fallbackauthdialog.js where we explicitly ask to users to login but since I'm using shared runtime the fallbackdialog.html never loads, it gives blank pop up ..

Is it possible to implement SSO and shared runtime at same time that works in teams desktop app as well?
Please answer the following questions before submitting an issue.

Steps to Reproduce

Please provide detailed steps for reproducing the issue.

1. update the manifest file to run in shared runtime
2. Get access token by clicking button in task pane in Teams desktop app
3. Fallback dialog does not work

Context

Please provide any relevant information about your setup. This is important in case the issue is not reproducible except for under certain conditions.
Even when

• Operating System:
• Node version:
• Office version:
• Tool version:

Failure Logs

Please include any relevant log snippets, screenshots or code samples here.

Read the manifest's shared-runtime configuration and fallbackauthdialog.js, then reproduce the numbered flow in the Teams desktop app. Done means documenting whether SSO can obtain a token there and, when fallback is needed, whether fallbackdialog.html loads instead of showing a blank pop-up.