Currently, when we click on the file attachment in the email file, the attachment opens a new viewer in the separate new window which is quite inconvenient for implementing workflows that require a user to stay on the same page where an initial file is displayed.
A few acceptance criteria are highlighted:
When user click on the attachment link viewer should be recreated in the same container it was embedded into
Viewer interface should indicate to a customer that attachment is viewed currently
Back button should appear in the interface to give user an option to go back to the original file