• Mobile

Thunderbird Mobile Progress Report: May 2025

Thunderbird for iOS

We’re growing a few more stars! We’re so happy to hear there is great interest in Thunderbird for iOS, and hope to reach a stage soon where you all can be more involved. Thank you, also, to those of you who’ve submitted an increasing number of ideas via Mozilla Connect.

Todd has been preparing the JMAP implementation for iOS, which will allow us to test the app with real data. We’re exploring the possibility of releasing the first community TestFlight a bit earlier by working directly with in-memory live data instead of syncing everything to a database upfront. The app may crash if your inbox has 30GB of email, but this approach should help us iterate more quickly. We still believe offline-first is the right path, and designing a database that supports this will follow soon after.

Further we’ve set up the initial localization infrastructure. This was surprisingly easy using Weblate’s translation propagation feature. We simply needed to add a new component to our Android localization project that pulls from the iOS repository. While Weblate doesn’t (yet?) auto-propagate when the component is set up, if there are changes across iOS and Android in the future, the strings will automatically apply to both products. 

Thunderbird for Android

We spent a lot of time thinking about the beta and making adjustments. Fast forward to June, we’re still experiencing a number of crashes. If you are running the beta, please report crashes and try to find out how to trigger them. If you are not using Beta, please give it a try and report back on the beta list or issue tracker. We’d greatly appreciate it! Here are a few updates worth noting for the month of May:

• Some folks on beta may have noticed the “recipient field contains incomplete input” error which kept you from sending emails. We’ve noticed as well, and halted the rollout of 11.0b1 on app stores where supported. Shamim fixed this issue for 11.0b2.
• Another important issue was when attaching multiple issues, only one image would be attached. This happens all the way back to 10.0, and we’ll release a 10.1 that includes this fix. Again thank you to Shamim!
• Final round of fixes from Shamim: new mail notifications can be disabled again, we have a bunch of new tests and refactoring, we have a few new UI types for the new preference system that Wolf created.
• Timur Erofeev solved a crash on Android 7 due to some library changes in dependency updates we didn’t anticipate
• Wolf is getting closer to finishing the drawer updates that we’re excited to share in a beta soon. He has also been working diligently to remove some of the crashes we’ve been experiencing on beta due to the new drawer and some of the legacy code it needs to fall back to. Finally, as we’re venturing into Thunderbird for iOS, Wolf has been thinking about the KMP (Kotlin Multiplatform) approach and added support to the Thunderbird for Android repository. He will soon separate a simple component and set things up so we can re-use it from Thunderbird for iOS.
• Rafael and Marcos have fixed some issues with the system bar appearing transparent. The issue has been very persistent, we’re still getting reports of cases where this isn’t yet resolved.
• Philipp has fixed an issue for our release automation to make sure the changelog doesn’t break on HTML entities.

I also wanted to highlight the new Git Commit Guide that Wolf created to give us a little more stability in our commits and set expectations for pull requests. We have a few more docs coming up in June, stay tuned. 

You could be on this list next month, please get in touch if you’d like to help out!

—
Philipp Kewisch (he/him)
Thunderbird Mobile Engineering | Mozilla Thunderbird