Use eSoftTools PST to MBOX Converter Software to convert your PST file to Thunderbird. Outlook PST files can be easily converted to MBOX files by using this fantastic tool. The tool has a user-friendly interface, so it's easy to use for non-technical users. There is a demo version of the tool is available here, which provides a live preview of PST emails and folders. All Outlook 2019, 2016, 2013, 2010, 2007, 2003, and previous versions are all compatible. You can convert up to 25 emails per folder in this demo version.
Visit here:- Import PST File in Thunderbird