The easiest way to migrate Roundcube emails into Thunderbird is by using Yota Roundcube Backup Tool. This software offers smooth migration of emails, contacts, and attachments. It comes with a batch migration option to move multiple emails at once. You can also preview and select specific emails before migration. The tool ensures all email properties like subject, sender, and date remain intact. It supports unlimited mailbox sizes without any restrictions. The interface is clean and simple, making it easy for beginners. With its advanced features and fast performance, this is a reliable and easy way to import Roundcube to Thunderbird.