Extract all emails from the Inbox folder as self-contained HTML files packaged in a .zip archive. Inline images will be embedded as base64.
There are two separate things you can do here. Pick the one you need.
Read a mailbox you've been given delegated access to, right inside this app.
Register this app as a device and open the real Outlook web app in your browser. This is a completely separate process from shared mailbox access.