I suggest EmailSoftwares Thunderbird to EMLX Converter for the seamless transfer of Thunderbird messages to EMLX format. This tool assures an error-free conversion while keeping attachments, metadata, and folder hierarchy intact. It also supports batch conversion, so you can export multiple Thunderbird files all at once without any size restrictions. Users are allowed to do a manual selection of the files or they can go for auto-detection. Other options include naming conventions and support for all Windows versions. A free demo version is available for the general public to scan and preview convertible items before purchasing. It is the best solution to transfer Thunderbird mailboxes to Apple Mail.