Thank you for adding that link into your post! It has definitely helped to understand exactly what you are looking for. I apologize your Library does not show this. Being able to see if an image has been used in a previous sent email, is a feature only available in our older Legacy Newsletter Templates. You are currently working in our newest Third Generation Editor, where this feature has not yet been added. I apologize for any inconvenience this may cause. While there is not currently a time estimate for when this is available, I have submitted your feedback to the appropriate teams.
Frankie P. Community & Social Media Support
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