Thunderbird has a profile export. Despite many folk thinking settings is something that they should be able to import and export, they are not offered as accounts as structured data and they are not portable, except in the context of the profile they were created with. Hence profile import and export.

Tools menu > export.

And just *WHY* not? If the application can read the settings in, there should be a way to interpret them and put them out as a YAML or JSON file. If Firefox can sync browser data and configuration, or Google/Apple/Microsoft can manage to synchronize profiles on their cr*p and closed systems, then why not something with a presumably open specification.

And just *WHY* not?

Because the developers chose another way. See https://bugzilla.mozilla.org/show_bug.cgi?id=271863

All the "Export" tool does is just make a dump of the entire profile to a ZIP file. I could do the same thing by manually copying over the profile directory. It's especially not helpful if you have a lot of data in your mail directories (over 2G). This is where you would want to create a new profile and populate the account settings, and then manually copy your [profile]/Mail and [profile]/ImapMail directories over once the profile is made. Would be a whole lot smaller 'export' file. Also with an optional switch to export passwords (I would say it should be the non-default option as well).

Now, the "help | Troubleshooting Information" is *almost* what you would need to at least manually re-create the accounts. But you can't print/export that page in the format it displays in (much cleaner on-screen than the excessively long printout shows up as), *plus* various settings show up as numbers rather than actual configuration screen values (such as "Authentication method" showing up as "3" when you print them, rather than showing "normal password").