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State Of The Bird: Thunderbird Annual Report 2023-2024

We’ve just released Thunderbird version 128, codenamed “Nebula”, our yearly stable release. So with that big milestone done, I wanted to take a moment and tell our community about the state of Thunderbird. In the past I’ve done a recap focused solely on the project’s financials, which is interesting – but doesn’t capture all of the great work that the project has accomplished. So, this time, I’m going to try something different. I give you the State of the Bird: Thunderbird Annual Report 2023-2024.

Before we jump into it, on behalf of the Thunderbird Team and Council, I wanted to extend our deepest gratitude to the hundreds of thousands of people who generously provided financial support to Thunderbird this past year. Additionally, Thunderbird would like to thank the many volunteers who contributed their time to our many efforts. It is not an exaggeration to say that this product would not exist without them. All of our contributors are the lifeblood of Thunderbird. They are the beacons shining brightly to remind us of the transformative power of open source, and the influence of the community that stands alongside it. Thank you for not just being on this journey with us, but for making the journey possible.

Supernova & Nebula

Thunderbird Supernova 115 blazed into existence on July 11, 2023. This Extended Support Release (ESR) not only introduced cool code names for releases, but also helped bring Thunderbird a modern look and experience that matched the expectation of users in 2023. In addition to shedding our outdated image, we also started tackling something which prevented a brisk development pace and steady introduction of new features: two decades of technical debt.

After three years of slow decline in Daily Active Users (DAUs), the Supernova release started a noticeable upward trend, which reaffirms that the changes we made in this release are putting us on the right track. What our users were responding to wasn’t just visual, however. As we’ve noted many times before – Supernova was also a very large architectural overhaul that saw the cleanup of decades of technical debt for the mail front-end. Supernova delivered a revamped, customizable mail experience that also gave us a solid foundation to build the future on.

Fast forwarding to Nebula, released on July 11, 2024, we built upon many of the pillars that made Supernova a success. We improved the look and feel, usability, customization and speed of the mail experience in truly substantial ways. Additionally, many of the investments in improving the Thunderbird codebase began to pay dividends, allowing us to roll in preliminary Exchange support and use native OS notifications.

All of the work that has happened with Supernova and Nebula is an effort to make Thunderbird a first-class email and productivity tool in its own right. We’ve spent years paying down technical debt so that we could focus more on the features and improvements that bring value to our users. This past year we got to leverage all that hard work to create a truly great Thunderbird experience.

K-9 Mail & Thunderbird For Android

In response to the enormous demand for Thunderbird on a phone, we’ve worked hard to lay a solid foundation for our Android release. The effort to turn K-9 Mail into something we can confidently call a great Thunderbird experience on-the-go is coming along nicely.

In April of 2023, we released K-9 6.600 with a message view redesign that brought K-9 and Thunderbird more in line. This release also had a more polished UI, among other fixes, improvements, and changes. Additionally, it integrated our new design system with reusable components that will allow quicker responses to future design changes in Android.

The 6.7xx Beta series, developed throughout 2023, primarily focused on improving account setup. The main reason for this change is to enable seamless email account setup. This also started the transition of K-9’s UI from traditional Android XML layouts to using the more modern and now recommended Jetpack Compose UI toolkit, and the adoption of Atomic Design principles for a cohesive, intuitive design. The 6.710 Beta release in August was the first to include the new account setup for more widespread testing. Introducing new account setup code and removing some of the old code was a step in the right direction.

In other significant events of 2023, we hired Wolf Montwé as a senior software engineer, doubling the K-9 Mail team at MZLA! We also conducted a security audit with 7ASecurity and OSTIF. No critical issues were found, and many non-critical issues were fixed. We began experimenting with Material 3 and based on positive results, decided to switch to Material 3 before renaming the app. Encouraged by our community contributors, we moved to Weblate for localization. Weblate is better integrated into K-9 and is open source. Some of our time was also spent on necessary maintenance to ensure the app works properly on the latest Android versions.

So far this year, we’ve shipped the account setup improvements to everyone and continued work on Material 3 and polishing the app in preparation for its transition to “Thunderbird for Android.” You can look at individual release details in our GitHub repository and track the progress we’ve made there. Suffice to say, the work on creating an amazing Android experience has been significant – and we look forward to sharing the first true Thunderbird release on Android in the next few months.

Services and  Infrastructure

In 2023 we began working in earnest on delivering additional value to Thunderbird users through a suite of web services. The reasoning? There are some features that would add significant value to our users that we simply can’t do in the Thunderbird clients alone. We can, however, create amazing, open source, privacy-respecting services that enhance the Thunderbird experience while aligning with our values – and that’s what we’ve been doing.

The services that we’ve focused on are: Appointment, a calendar scheduling tool; Send, an encrypted large-file transfer service; and Thunderbird Sync, which will allow users to sync their Thunderbird settings between devices (both desktop and Android).

Thunderbird Appointment enables you to plan less and do more. You can add your calendars to the service, outline your weekly availability and then send links that allow others to grab time on your schedule. No more long back-and-forth email threads to find a time to meet, just send a link. We’ve just opened up beta testing for the service and look forward to hearing from early users what features our users would like to see. For more information on Thunderbird Appointment, and if you’d like to sign up to be a beta tester, check out our Thunderbird Appointment blog post. If you want to look at the code, check out the repository for the project on GitHub.

The Thunderbird team was very sad when Firefox Send was shut down. Firefox Send made it possible to send large files easily, maybe easier than any other tool on the Internet. So we’re reviving it, but not without some nice improvements. Thunderbird Send will not only allow you to send large files easily, but our version also encrypts them. All files that go through Send are encrypted, so even we can’t see what you share on the service. This privacy focus was important in building this tool because it’s one of our core values, spelled out in the Mozilla Manifesto (principle 4): “Individuals’ security and privacy on the internet are fundamental and must not be treated as optional.”

Finally, after many requests for this feature, I’m happy to share that we are working hard to make Thunderbird Sync available to everyone. Thunderbird Sync will allow you to sync your account and application settings between Thunderbird clients, saving time at setup and headaches when you use Thunderbird on multiple devices. We look forward to sharing more on this front in the near future.

2023 Financial Picture

All of the above work was made possible because of our passionate community of Thunderbird users. 2023 was a year of significant investment into our team and our infrastructure, designed to ensure the continued long-term stability and sustainability of Thunderbird. As previously mentioned these investments would not have been possible without the remarkable generosity of our financial contributors.

Contribution Revenue

Total financial contributions in 2023 reached $8.6M, reflecting a 34.5% increase over 2022. More than 515,000 transactions from over 300,000 individual contributors generated this financial support (26% of the transactions were recurring monthly contributions).

In addition to that incredible total, what stands out is that the majority of our contributions were modest. The average contribution amount was $16.90, and the median amount was $11.12.

We are often asked if we have “super givers” and the refreshing answer is “no, we simply have a super community.” To underscore this, consider that 61% of giving was $20 or less, and 95% of the transactions were $35 or less. The number of transactions $1000 and above accounted for only 56 transactions; that’s effectively 0.0007% of all contribution transactions.

And this super community helping us sustain and improve Thunderbird is very much a global one, with contributions pouring in from more than 200 countries! The top five giving countries — Germany, the United States, France, the United Kingdom, and Japan — accounted for 63% of our contribution revenue and 50% of transactions. We believe this global support is a testament to the universal value of Thunderbird and the core values the project stands for.

Expenses

Now, let’s talk about how we’re using these funds to keep Thunderbird thriving well into the future. 

As with most organizations, employee-related expenses are the largest expense category. The second highest category for us are all the costs associated with distributing Thunderbird to tens of millions of users and the operations that help make that happen. You can see our spending across all categories below:

The Importance of Supporting Thunderbird

When I started at Thunderbird (in 2017), we weren’t on a sustainable path. The cost of building, maintaining and distributing Thunderbird to tens of millions of people was too great when compared against the financial contributions we had coming in. Fast forward to 2023 and we’re able to not only deliver Thunderbird to our users without worrying about keeping the lights on, but we are able to fix bugs, build new features and invest in new platforms (Android). It’s important for Thunderbird to exist because it’s not just another app, but one built upon real values.

Our values are:

• We believe in privacy. We don’t collect your data or spy on you, what you do in Thunderbird is your business, not ours.
• We believe in digital wellbeing. Thunderbird has no dark patterns, we don’t want you doomscrolling your email. Apps should help, not hurt, you. We want Thunderbird to help you be productive.
• We believe in open standards. Email works because it is based on open standards. Large providers have undermined these standards to lock users into their platforms. We support and develop the standards to everyone’s benefit.

If you share these values, we ask that you consider supporting Thunderbird. The tech you use doesn’t have to be built upon compromises. Giving to Thunderbird allows us to create good software that is good for you (and the world). Consider giving to support Thunderbird today.

2023 Community Snapshot

As we’ve noted so many times in the previous paragraphs, it’s because of Thunderbird’s open source community that we exist at all. In order to better engage with and acknowledge everyone participating in our projects, this past year we set up a Bitergia instance, which is now public. Bitergia has allowed us to better measure participation in the community and find where we are doing well and improving, and areas where there is room for improvement. We’ve pulled out some interesting metrics below.

For reference, Github and Bugzilla measure developer contributions. TopicBox measures activity across our many mailing lists. Pontoon measures the activity from volunteers who help us translate and localize Thunderbird. SUMO measures the impact of Thunderbird’s support volunteers who engage with our users and respond to their varied support questions.

Contributor & Community Growth

Thank You

In conclusion, we’d simply like to thank this amazing community of Thunderbird supporters who give of their time and resources to create something great. 2023 and 2024 have been years of extraordinary improvement for Thunderbird and the future looks bright. We’re humbled and pleased that so many of you share our values of privacy, digital wellbeing and open standards. We’re committed to continuing to provide Thunderbird for free to everyone, everywhere – thanks to you!