https://community.canvaslms.com/docs/DOC-26370-how-do-i-use-the-inbox-as-an-instructor
The Inbox is split into two panels and displays messages chronologically. You can view and reply to conversations and sort them by course or inbox type. The Inbox itself does not have any file size limits; however, attachments added to a conversation are included in the sender’s personal files. See also CANVAS Essentials course in asynchronous page.
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