After exploring plans of ditching the Thunderbird project in the lap of another organization, the Mozilla Foundation has decided to keep its infamous email client under its wing for a little longer, albeit in a new role, and not as a core project.

First plans to find Thunderbird another home were publicly expressed in December 2015 by Mitchell Baker, Executive Chairwoman of the Mozilla Foundation and Mozilla Corporation.

Back then, Baker and Mozilla were struggling to cope with Firefox's plummeting market share, which indirectly meant fewer profits from browser searches and fewer profits for the organization overall.

While Baker didn't specifically say she wanted Mozilla to ditch Thunderbird, he expressed an opinion about the Foundation finding Thunderbird a new home with a more dedicated community (and a place on someone else's budget).

Thunderbird left for dead since 2012

At the time, the 11-year-old project was effectively dead, as Mozilla had stopped adding new features in Thunderbird three years before, in 2012, only delivering security-related fixes.

As Baker had suggested, plans were later set in motion to find Thunderbird a new home. Nine months later, a report from Simon Phipps, a consultant in the world of open source and digital rights, suggested three potential homes for the Thunderbird email client.

Initial candidates were the Software Freedom Conservancy (manager of Git, BusyBox, Samba, and Wine), The Document Foundation (managers of the LibreOffice office suite), and a third option that included the Mozilla Foundation itself, but in a new role, where the Thunderbird project would be set up as a separate entity.

Other candidates listed in the report, but rejected, included the Apache Foundation, the GNOME Foundation, and Software In The Public Interest.

Plans to ditch Thunderbird rallied the community

Many in the Thunderbird community viewed this report and Mozilla's decision to seek the email client's future elsewhere as a metaphorical guillotine over Thunderbird's neck.

Soon after that, Thunderbird development picked up again, and the email client started receiving new features, powered by an influx of developers that didn't want to see their favorite client fall to the side.

In an announcement published today, the Mozilla Foundation appears to have reached a decision regarding the email client's future, one that many willl probably like.

The Mozilla Foundation has agreed to continue as Thunderbird’s legal, fiscal and cultural home, with the following provisos:



A) The Thunderbird Council and the Mozilla Foundation executive team maintain a good working relationship and make decisions in a timely manner.

B) The Thunderbird Council and the team make meaningful progress in short order on operational and technical independence from Mozilla Corporation.

C) Either side may give the other six months notice if they wish to discontinue the Mozilla Foundation’s role as the legal and fiscal host of the Thunderbird project.

What the new agreement means

Under this new agreement, the Thunderbird team will exist as a separate entity outside of the Mozilla family. The Thunderbird Council (as its called right now) will be a new legal entity and have to seek independent funding, either from donations or corporate sponsors, but the Mozilla Corporation will also provide some financial support for the time being.

This new relationship between Mozilla and the Thunderbird team will be contractual. For example, Mozilla will rent the Thunderbird group the right to use the Thunderbird trademark, or some of its technology and servers. As time goes by, the Thunderbird Council will take over more and more Thunderbird operational details from the Mozilla Foundation.

At the technical level, for the foreseeable future, Thunderbird will continue to operate on Gecko, the same engine that currently powers Firefox.

Mozilla is in the process of moving Firefox to a new engine, built using the Rust programming language. Mozilla says that while Thunderbird will continue to work on Gecko, certain parts of the Thunderbird code will eventually cease to be supported.

As Mozilla is the only one supporting Gecko, this means that in the coming future, if users like it or not, Thunderbird will eventually have to move to a new engine revolving around current web technologies.

Nonetheless, for the time being, the project is safe. Either way, if this Mozilla side-project fails, Mozilla has reserved the right to pull out of this new arrangement and allow the Thunderbird team to seek a new home at another open-source organization.

According to Mozilla, Thunderbird currently has around 25 million users worldwide.