Betterbird is a free, donation-funded fork of Mozilla Thunderbird with extra features and faster bug fixes. See what it offers.
Betterbird, available at betterbird.eu, is a free and open-source email client built as a soft fork of Mozilla Thunderbird. The project is led by Jorg Knobloch, a longtime Thunderbird contributor who served as Thunderbird's first paid employee and its maintainer and release engineer from roughly 2016 to 2019, contributing more than 2,000 commits to the official Thunderbird codebase.
Betterbird launched publicly around 2022 after Knobloch parted ways with the official Thunderbird project over concerns about quality assurance and bug-triage practices, and has since released versions in parallel with Thunderbird's Extended Support Release (ESR) cycle.
Unlike a hard fork, Betterbird pulls its source directly from Mozilla's Thunderbird repositories and layers a public, transparent set of patches on top, published in a GitHub repository, with the stated goal of eventually contributing improvements back upstream to Thunderbird itself. It is distributed under the same MPL-2.0 license as Thunderbird and runs on Windows, macOS, and Linux, sharing the same profile format so users can switch between the two clients on the same version without conversion.
Notable features layered on top of stock Thunderbird include a multi-line message list view, an improved system tray tooltip on Linux that shows new messages by folder, more powerful search with support for excluding criteria and regular expressions, and a feature that remembers recently used attachments so files can be reattached without re-browsing folders.
Betterbird has no purchase price and no subscription fee; the project is entirely funded by voluntary donations processed through Stripe, PayPal, and regional bank transfer options across North America, Europe, the UK, Canada, and Australia and New Zealand. Reports indicate fewer than 2 percent of Betterbird's users financially support the project, with donations split roughly evenly between North America and Europe, particularly Germany.
Yes, Betterbird is free and open-source, funded entirely through voluntary donations.
Betterbird is led by Jorg Knobloch, a former Thunderbird maintainer and release engineer.
Betterbird is a soft fork that sources code directly from Mozilla's Thunderbird repositories and publishes its patches publicly on GitHub, closely tracking Thunderbird's ESR releases.
Yes, both clients share the same profile format, so users can switch between them on the same version without conversion.
Betterbird runs on Windows, macOS, and Linux.
Yes, Betterbird's source is pulled directly from Mozilla's Thunderbird repositories, with additional patches layered on top.
Yes, the project's stated goal is to submit its improvements upstream so Thunderbird itself can eventually benefit.
Betterbird is funded entirely by voluntary donations via Stripe, PayPal, and regional bank transfers.