Thunderbird
Cross-platform mail, calendar, and RSS client with extension support.
Why it is included
Long maintenance, large user base, and continuous modernization—practical alternative to web-only mail.
Best for
Power users managing multiple accounts and folders.
If you use Windows, Mac, or paid tools
Mail alternative to Microsoft Outlook, Apple Mail, and web-only Gmail for desktop IMAP/JMAP.
Strengths
- Filtering
- OpenPGP paths
- Extensions
Limitations
- Mobile parity still evolving vs incumbents
Good alternatives
Geary
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