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Thunderbird email client is Go for new plumage in July

Supernova will prove open source project is not dead – just pining for an enormo-revamp

The Thunderbird email client – once Mozilla's most prominent project other than the Firefox browser – is being completely overhauled ahead of its major July release 115 dubbed "Supernova."

Product design manager Alessandro Castellani last week blogged about plans for the release. He also explained the complex history of the client, which has seen it reach a state he described as akin to "an old, fragile LEGO tower" that looks like it could topple at any moment.

The process that led the app to that state started in 2012 when the Mozilla Foundation stopped focussing on Thunderbird and moved it to a community-driven development model. While plenty of developers volunteered to work on the project, Castellani wrote that "many volunteer contributors with varying tastes … resulted in an inconsistent user interface without a coherent user experience."

Making life harder was the app's structure – or lack thereof. Castellani described Thunderbird as "literally a bunch of code running on top of Firefox. All the tabs and sections you see in our applications are just browser tabs with a custom user interface."

With developers submitting their own ideas, and no central control, "the lack of constant upstream synchronization with Firefox caused the inability to build and release Thunderbird for months at a time."

The Mozilla Foundation addressed that, to some extent, by moving Thunderbird into a wholly owned subsidiary called MZLA Technologies Corporation that was permitted to monetize the app.

That move meant that paid developers started work on Thunderbird. While that was welcome, it also alienated volunteers.

Not all volunteers, though: Castellani wrote that he and the other paid Thunderbird devs are in touch with the community and work hard to listen to its concerns, but that MZLA employees are the ones who make final decisions about what happens to Thunderbird – "like a normal company."

Among their decisions is that Thunderbird needs an overhaul because "Simply 'adding stuff on top' of a crumbling architecture is not sustainable, and we can't keep ignoring it."

"With this year's release of Thunderbird 115 'Supernova,' we're doing much more than just another yearly release," Castellani wrote. "It's a modernized overhaul of the software, both visually and technically. Thunderbird is undergoing a massive rework from the ground up to get rid of all the technical and interface debt accumulated over the past ten years."

Supernova will deliver "A UI that looks and feels modern … aiming at offering a simple and clean interface for 'new' users, as well as the implementation of more customizable options with a flexible and adaptable interface to allow veteran users to maintain that familiarity they love."

Castellani also detailed the following "primary objectives" for the next three years of Thunderbird development:

  • Make the code base leaner and more reliable, rewrite ancient code, remove technical debt;
  • Rebuild the interface from scratch to create a consistent design system, as well as developing and maintaining an adaptable and extremely customizable user interface;
  • Switch to a monthly release schedule.

Castellani set low expectations for the above efforts, because while Thunderbird has "a bit more than a dozen core developers," Firefox has hundreds. And those coders are "constantly changing and improving things on a daily basis."

"So, you can imagine how many times per week things suddenly break in Thunderbird because a C++ interface was renamed, or an API was deprecated, or a building library was upgraded. Keeping up with the upstream changes is not a simple task, and on some occasions it takes up most of our days."

But Castellani and his team will soldier on, and plan what he described as "the constant addition of new features that some of our competitors have had for years, as well as the creation of some amazing and innovative solutions that will improve everyone's experience."

Which will probably be welcome. Email marketing platform Litmus rates Apple as the world's dominant email client vendor, with almost 59 percent market share, ahead of Gmail clients at 28 percent. Microsoft's Outlook accounts for four-and-a-half percent, ahead of fourth-placed Yahoo! Mail's three percent.

Web-watching firm statcounter pegs Mozilla's Firefox market share at three percent – a level that allows it to secure funding from Google and others.

Castellani's post reveals that Thunderbird's developers are working on "more services … to increase our revenue stream." So perhaps three percent market share for Thunderbird could see it achieve Castellani's stated goal of becoming "the best personal and professional communication application out there!"

Castellani offers more detail in the video below. ®

YouTube Video

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