On the domain permission add the URL to your SharePoint portal to the Single-Sign-On filed.This app already exists on your azure and is used also by the SPFx web parts on Microsoft Teams On the domains and permissions scroll down and add the following value to the AAD App-ID field.

On the domains and permissions add the following domains manually by clicking in the Add button.Leave the website url with the default SharePoint link The link to the actual page is added as a relative URL after the query string dest. Edit your tabs and modify the content url to the following format.Start by opening the app on the app studio.Since the original video describe the process as a no code solution I’m providing the steps The modifications made to the solution are documented here and you should be able to use them without any problem, in the following image you have highlighted all the necessary additions to the manifest. If you want to see how this can be done watch the original video here. Note: This article does not cover the process of creating the app.

Microsoft teams app sign in error