To view Thunderbird emails into HTML format, users can convert them into HTML format using the WholeClear Thunderbird to HTML Converter. This tool helps save emails from Thunderbird as clean, readable HTML files without changing the original content. It keeps the email layout, links, and attachments safe during the process. Users simply load their Thunderbird files, pick a location to save the HTML files, and start the conversion. It's fast, easy to use, and doesn't need technical knowledge. Even large numbers of emails can be converted at once. This makes it great for backup, sharing, or offline viewing. A free demo version is available to try before purchasing.