Forward-looking: In recent years, Thunderbird has turned into a successful stand-alone software product thanks to the newly-established MZLA subsidiary. Donations are booming, but Mozilla plans to further increase the program's chance for survival with additional revenue streams.

Mozilla Thunderbird is almost 20 years old, and the open-source company is working hard on the future of one of the most popular offline mail clients available on the market. The future of Thunderbird is brighter than ever, as developers are busy with modernizing the program's ancient codebase with a leaner and more reliable approach and a new interface rebuilt from scratch.

As the newly-published Financial Report for 2022 clearly highlights, Mozilla Thunderbird isn't in survival mode anymore. Thanks to the dedicated core team of developers, a "passionate community" of users, and "generous donors," Thunderbird has been kept alive during some difficult times. For donations alone, 300,000 users contributed more than $6.4 million in a single year.

Donations represent more than 99.9% of Thunderbird's annual revenue, the aforementioned report states, which means that users believe in MZLA's mission and want to see the email client thrive. Not just in 2023 but "decades into the future," Mozilla says.

MZLA can now count on a team of 24 people, which is vastly improving the Thunderbird desktop experience. Larger architecture changes are coming, with some of the improvements included in the 115 "Supernova" release scheduled for this summer and a larger pay-off in 2024. As a matter of fact, in 2022 Mozilla spent 79,8% of its total revenue on paying developers and other employees running the business.

Donations aside, MZLA has now decided to expand "beyond the core experience" Thunderbird users are accustomed to. The company is thinking about "additional sources of revenue," providing new tools and services to increase productivity which users will have to pay for. Some of these additions will be introduced later this year, albeit in "Beta status."

MZLA tried to reassure its userbase, stating that the company has "no plans to charge money" for the experience Thunderbird provides right now, nor do they plan to remove features and "charge for them later." In layman terms, MZLA wants to follow the same route taken with Firefox, as Mozilla began integrating some paid (and totally optional) offerings in its open-source browser starting with Mozilla VPN.