Find and Merge Duplicates within a certain group.

Posting on behalf of D. Griffin:

"Since IOS 15 has made the topic of improving email deliverability, here are 2 things I would like to see:

1. The ability to create a group mailing my contacts active in the past 90 days + previous customers wihout needing to make an exclusion list, the fix ithis problem manually with tagging.

2. The ability to find and merge duplicate emails for only my active send list and not my entire database. Merging is very time consuming and what do I care of inactive users I no longer mail are have duplicate emails. Presently I can do this only for my whole list."