Unable to Give Full Control to SharePoint Online Add-in

Question

I registered an add-in on my SharePoint Online site collection by going to [Site Collection URL]/_layouts/15/AppRegNew.aspx
Noted Client ID and Client Secret. Trying to give it FullControl here: [Site Collection URL]/_layouts/15/AppInv.aspx by entering the following XML:

<AppPermissionRequests AllowAppOnlyPolicy="true">  
   <AppPermissionRequest Scope="Site Collection URL" 
    Right="FullControl" />
</AppPermissionRequests>

On 'Do you trust the app page' it does not ask me to give it Full Control but only the following:
Let it share its permissions with other users.
Let it access basic information about the users of this site.

What am I missing?

Answer 1

The site collection scope url in permission XML should be :

 http://sharepoint/content/sitecollection  

You could have a try with this url.

More information about SharePoint APP registration for your reference:
https://learn.microsoft.com/en-us/sharepoint/dev/solution-guidance/security-apponly-azureacs
https://learn.microsoft.com/en-us/sharepoint/dev/sp-add-ins/add-in-permissions-in-sharepoint

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