This feature request is working its way through the backlog queue. No new details are available yet.
Right now, I cannot use document library (add SharePoint tab) from the root SharePoint site (https://organizationname.sharepoint.com)
I opened a ticket with the support team and they tell me "unfortunately the feature of enabling SharePoint root site collection in Microsoft Teams cannot be enable; this is something that cannot be modified by design."IT supported this idea ·