Outlook: browser Back button goes back to primary inbox when readying shared mailbox

When reading a message inside a shared mailbox on outlook web, the "back" button the browser does not behave as expected.

If I've opened an email in one of my shared mailboxes, or groups, pressing  the "back" button will go back to the primary inbox, not the shared mailbox.

I have tried accessing other folders (such as "sent items") in my primary mailbox, and the back button works correctly for that.