We apologize for this less than stellar experience. You should be able to preview these attachments in the Attachments tab, as they should pull in from your emails, and you should be able to see them on the mobile app, but we haven’t added functionality to preview them directly on the email in the web app.
We’ll add this to our list and get the experience improved in a future update.
simple fix show thumbnail on hover so we don't have to go to attachments all the time
it makes us waste so much time, plush the attachment page we have to constantly
zoom on the page because they are so small when there's so much space to use is not productive