Remove Duplicate Emails from Thunderbird, Thunderbird is a free email client created by Mozilla. Many small businesses and individuals use it as their primary email client for sending and receiving emails. However, it occasionally copies duplicate emails, increasing the size of the mailbox. Thunderbird becomes slow as a result of the large mailbox size, causing numerous problems for the user. Remove Duplicate Emails from Thunderbird, In this post, we will look at the causes of duplicate emails in Thunderbird. We will also learn how to delete duplicate emails from Thunderbird in a straightforward manner. If you use Thunderbird and are experiencing the same problem, this post will be useful to you.