Thunderbird
Since the release of its first official version in 2004, Thunderbird has established itself as a leading email program in the open-source community, despite a tumultuous history. The Mozilla Foundation, which also maintains the Firefox browser, ceased support for the development of Thunderbird in 2012; however, the project not only survived but made a fresh start, thanks mainly to its community—reportedly 20 million users—and their donations.
In 2020, a subsidiary named MZLA Technologies Corporation was founded for Thunderbird. In 2023, version 115 “Supernova” was released, bringing modernization to the user interface. In 2024, version 128 “Nebula” followed, overhauling the codebase based on the Rust programming language.
Advantages
Thunderbird is available not only for Linux but also for Windows and macOS; profiles can be copied and used across platforms. Additionally, since 2024, the Android app K-Mail has been released under the Thunderbird label and is gradually being made compatible with the desktop version.
Another advantage is the extensibility of the program through add-ons, similar to what is known from the Firefox browser. Add-ons that allow Thunderbird to be enhanced into a Personal Information Manager (PIM) are now part of the core, giving Thunderbird the potential to replace Microsoft Outlook.
User interface and program functions
The “Card View” layout introduced in 2023 resembles web applications like Gmail and offers a three-column view; however, traditionalists can easily switch back to the old table layout.
Using the icons in the left sidebar, you can select the desired application context, such as email, address book, calendar, tasks, or chat. Depending on the context, Thunderbird then displays an appropriate dropdown menu.
Thunderbird’s core component, the email client, allows for managing multiple accounts (POP, IMAP, SMTP) either separately or in a unified inbox. Additionally, multiple address books can be maintained, not just locally: via the address book icon on the left side of the screen, you can also integrate contacts from the web using LDAP or CardDAV. Email encryption, previously available only through a plugin (Enigmail), is now a standard feature of Thunderbird.
The calendar extension Lightning has been firmly integrated since version 78. It works with both local calendars and those online (CalDAV, iCal, or WCAP). The Google Calendar Provider is available as an extension. The Thunderbird developers are still working on support for Microsoft’s Exchange protocol, but the Owl extension has received positive reviews.
Speicherort und Backup
All emails, address books, and account settings, as well as most plugins, can be conveniently archived and migrated to another computer by copying the profile folder. If Thunderbird is installed as a Snap, you can find this folder under ~/snap/thunderbird/common/, otherwise under ~/.thunderbird. The name of the profile folder typically consists of a random combination of letters and numbers with the suffix .default. If there are also orphaned profiles, you can determine which one was used last by looking at the modification date.
Installation
Like the Firefox Browser, Thunderbird is officially distributed as a Snap – even if you issue the typical apt install command:
sudo apt install thunderbird
Alternatives
Geary ist a slim e-mail-client for the Gnome Shell; at Elementary OS it is known under the name Pantheon Mail. Gnome ships Evolution, an alternative to Microsoft’s Outlook, which integrates e-mail, contacts, calender, tasks and notes. KDE has a PIM (personal information manager) of its own called Kontact, which uses Kmail for e-mail.