The future of Thunderbird

Mozilla surprised Thunderbird fans on July 6 when it announced that it was pulling developers from the project. Mozilla says it will continue to test, patch, and maintain future releases — including stability and security fixes — while letting community members guide development of new features. But that promise did not prevent a slew of headlines reporting that the email client was being put out to pasture. A number of Mozilla developers have subsequently commented on the decision, helping to clarify the outlook for the future somewhat, if not completely.

Mozilla chief Mitchell Baker posted the announcement on her blog, starting with the question "is Thunderbird a likely source of innovation and of leadership in today’s Internet life? Or is Thunderbird already pretty much what its users want and mostly needs some on-going maintenance?" The answer from Mozilla's upper echelons, evidently, is that the desktop email client is essentially feature-complete, and not likely to experience further innovations. Consequently, Mozilla as a whole is better off directing its engineering resources to its current "priority" projects.

Baker's post was interpreted by many to mean that Mozilla was halting development on Thunderbird, perhaps offloading control of the project to the open source community or otherwise attempting to get rid of the project without saying that it was getting rid of the project. Thunderbird would hardly be the first open source project to suffer such a fate, so a pessimistic take on the announcement is understandable. But the details that have emerged since the announcement paint a different picture.

Details, details

On July 7, Jb Piacentino posted an announcement to the tb-planning mailing list which covered the same ground as Baker's post. In it, he assured readers that the move was not the cessation of Thunderbird development:

Thunderbird developer Ludovic Hirlimann said on his blog that Thunderbird 14, 15, and 16 would all be released before the new plan takes effect, and that the new model's practical effect would be that "we won’t have the time to work on specking, developing and testing new features," although the team would still participate in the development process.

Details about the plan are described on the Mozilla wiki. The plan draws a distinction between the normal Thunderbird and the extended support release (ESR) version. Mozilla will focus on the Thunderbird ESR releases and associated security updates, while allowing other contributors to work on the standard Thunderbird trunk. Mozilla will continue to provide the testing and release infrastructure, and Mozilla staffers will serve as the release team. But the Mozilla staffers will not be tasked with introducing new features. ESR releases are guaranteed to receive security updates for one year, rolled out with Firefox ESR, on a six-week schedule.

Despite Piacentino's reassurances and the wiki's lengthier explanation, some on the list still interpreted the news in starkly different terms. For example, while Ben Bucksch took it to mean an end-of-life announcement, Charles Tanstaafl read the announcement to mean that Mozilla employees would "focus on stability and fixing many of the long standing bugs".

Others wanted more specifics on the new process. Kai Engert asked whether the arrangement meant that Thunderbird releases would be kept in sync with Firefox on shared components (including Gecko):

Concerns raised also included the fate of in-progress development work (such as the long awaited rewrite of Thunderbird's address book) and whether or not the outside community would be able to mentor Google Summer of Code (GSoC) projects, which have been a dependable source of new code in the past. The community has indeed played a major part in recent innovations, including the new "conversations" view extension, MIME handling, and the recent removal of RDF as a dependency. Mozilla's Mark Banner replied that Thunderbird's annual ESR releases would synchronize with the then-current Firefox release (including any Gecko updates), but that the intervening six-week security update releases would not roll in recent changes. The bulk of in-progress projects are slated to be completed before the new process begins, he added. Finally, he pointed out that Thunderbird community members had mentored past GSoC projects, so the process change should not interfere.

Email versus the web

Several Mozilla staffers commented about the announcement in blog posts of their own. Thunderbird developer Joshua Cranmer observed:

Cranmer did not bemoan this situation, however. He saw it as natural considering the growth of mobile email, and because "Mozilla's primary goal is to promote the Open Web." The assertion that the web — but not email — is Mozilla's central mission was also touched on in official channels. The wiki page states that the priority projects getting Mozilla's attention are "important web and mobile" efforts, "while Thunderbird remains a pure desktop only email client." Baker's blog post similarly noted that the project has "seen the rising popularity of Web-based forms of communications representing email alternatives to a desktop solution."

But Bucksch took issue with that notion in considerable detail, observing that if Thunderbird is losing out to web-based email, that constitutes a loss, because "Webmail is definitely not open. You're totally dependent on the features and limitations the provider offers [...] Privacy goes out the door with webmail. Even integrity: The ISP can even alter the message contents years after the fact, and I have no way to verify or prove this."

Mozilla's stated mission is "to promote openness, innovation and opportunity on the web, but Bucksch points out that its manifesto stakes out considerably broader principles about the openness of the Internet as a whole. Side-stepping for the moment why the organization has a separate "mission" statement and "manifesto" at all (much less inconsistent ones), the point is well-taken. If Thunderbird has failed to grab a majority of the world's email client share, what users are left with are proprietary OS-vendor clients on the desktop, or proprietary software services on the web. Mozilla Labs briefly toyed with a webmail client called Raindrop, but shuttered it before it left the experimental phase.

Perhaps competition from webmail clients is a side issue, and Mozilla is primarily readying itself to make a greater play for what it sees as the new email battleground on mobile devices, with its Boot-to-Gecko effort (which was recently renamed Firefox OS). Andrew Sutherland, a developer on Mozilla's forthcoming Firefox OS email client, told the tb-planning list that he and other team members were list subscribers, and were at least open to the possibility of collaborating with the Thunderbird community on compatibility features.

Despite the doomsday predictions that leaked out following the initial announcement, Mozilla's plans indicate that it is committed to testing and releasing Thunderbird for at least the next year or so (depending on the final release date of Thunderbird ESR 17). The distant future is less clear, but that could be said of many other projects. Anyone who doubts the ability of the Mozilla volunteer community to maintain a product needs only to look at Seamonkey, which continues to live on long after Mozilla lost interest. Still, Mozilla's second-class treatment of its email client is troubling for other reasons. Email itself may be relatively static, but IM, VOIP, and other communication methods are coming and going all the time, and Mozilla has not offered a consistent client story for them. If Firefox is Mozilla's only product, users' hope for an open web boils down to "hopefully the service providers will write open source web apps for foo" — which seems like a long shot.