To convert OST to MBOX Thunderbird you can try this OST to MBOX Converter software is one of the reliable answers that permits migration of multiple OST files to MBOX Thunderbird. This tool provides you rapid conversion ability. The third-party tool has simple and easy GUI Interface where both technical and Non-technical users easily access this Software.
It has wonderful users friendly interface and provide free demo version which permit the all users to see the preview of all convertible data.
Download and install this OST to MBOX converter software to easily convert the OST file to MBOX and other file formats i.e. MSG, PST, HTML, and EML file format. This software is really easy to use, you just need to do one click and you will get your conversion done within seconds. For more information, please visit here:- https://www.toolsbaer.com/ost-to-mbox-conversion/
If you want to convert OST to MBOX,Then you can simply go with ZOOK OST to MBOX Converter to convert OST to MBOX with attachments. It easily batch export Outlook OST to MBOX format for various MBOX based email clients such as Thunderbird, Mac Mail, Eudora, Entourage, etc. This enables user to import OST to Thunderbird, Mac Mail, etc. without any extra efforts. The tool easily supports OST file any Outlook editions such as Outlook 2016, 2013, 2010, 2007, 2003, etc. The software has so simple interface which itself explains the entire conversion process for any non-technical users and helps them to convert OST to MBOX with attachments users are offered to export 25 items from each folder of OST file to MBOX format.