Mozilla Thunderbird Backup Tool is a modern-day utility that securely allows users to back up and migrates Thunderbird emails to various file formats and email clients. Apart from this, it has some extensive functionalities that help users to optimize the whole backup process. Some of its prominent features are as follows: 1. It allows users to export Thunderbird emails to PST, PDF, CSV, EML, MSG, etc. 2. This advanced utility helps to migrate Thunderbird emails to Office 365, Gmail, Yahoo, Hotmail, iCloud, and various other IMAP-enabled email clients. 3. Users can also opt for its Mail Filter feature which helps them to select the specified mailboxes within a particular date range. 4. Additionally, it has the Remove Duplicate Mail feature to prevent multiple migrations of the same emails.