• Development

Thunderbird Monthly Development Digest – February 2025

Hello again Thunderbird Community! Despite the winter seeming to last forever and the world being in a state of flux, the Thunderbird team has been hard at work both in development and planning strategic projects. Here’s the latest from the team dedicated to making Thunderbird better each day:

Monthly Releases are here!

The concept of a stable monthly release channel has been in discussion for many years and I’m happy to share that we recently changed the default download on Thunderbird.net to point at our most feature-rich and up-to-date stable version. A lot of work went into this release channel, but for good reason – it brings the very latest in performance and UX improvements to users with a frequent cadence of updates. Meaning that you don’t have to wait a year to benefit from features that have been tested and already spent time on our more experimental Daily and Beta release channels. Some examples of features that you’ll find on the monthly release channel (but not on ESR) are:

• Linux System Tray
• Dark reader Support
• Folder compaction improvements
• Hundreds of UI enhancements
• ICS Import
• Calendar printing improvements
• Appearance settings UI
• Many, many more

Download it over the top of your ESR installation and get the benefits today!

Developing Standards

As privacy and security legislation evolves, the Thunderbird team often finds itself in the heart of discussions that have the potential to define industry solutions to emerging problems. In addition to the previously-mentioned research underway to develop post-quantum encryption support, we’re also currently considering solutions to EU laws (EU NIS2) that require multi-factor authentication be in place for critical digital infrastructure and services. We’re committed to solving these issues in a way that gives users and system administrators other options besides Google & Microsoft, and we’ll be sharing our thoughts on the matter soon, with the resulting decisions documented in our new ADR process.

For now, you can follow a healthy and colourful discussion on the topic of OAuth2 Dynamic Client Registration here.

Calendar UI Rebuild is underway

The long awaited UI/UX rebuild of the calendar has begun, with our first step being a new event dialog that we’re hoping to get into the hands of users on Daily via a preference switch. Turning the pref on will allow the existing calendar interface to launch the new dialog once complete. The following pieces of work have already landed:

• Dialog container
• Generic row container
• Calendar row
• Close button
• Generic subview
• Title

Keep track of feature delivery via the [meta] bug 

Exchange Web Services support in Rust

A big focus for February has been to grow our team so we’ve been busy interviewing and evaluating the tremendously talented individuals who have stepped forward to show interest in joining the team. In the remaining time, the team has managed to deliver another set of features and is heading toward a release on Daily that will result in most email features being made available for testing. Here’s what landed and started in February:

• Display refactor
• Basic testing framework
• Sync folder – delete
• Sync folder read/unread
• Integration testing
• Complete composition support (reply/forward)

Keep track of feature delivery here.

Account Hub

Since my last update, tasks related to density and font awareness, the exchange add-on and keyboard navigation were completed, with the details of each step available to view in our Meta bug & progress tracking. Watch out for this feature being rolled out as the default experience for the Daily build this week and on beta after the next merge on March 25th!

Global Message Database

The New Zealand team are in the middle of a work week to shout at the code together, have a laugh and console each other plan out work for the next several weeks. Their focus has been a sprint to prototype the integration of the new database with existing interfaces with a positive outcome meaning we’re a little closer to producing a work breakdown that paints a more accurate picture of what lies ahead. Onward!

In-App Notifications

Phase 3 of the project is underway to finalize our uplift stack and add in last-minute features! It is expected that our ESR version will have this new feature enabled for a small percentage of users at some point in April. If you use the ESR release, watch out for an introductory notification!

 Meta Bug & progress tracking.

New Features Landing Soon

Several requested features and fixes have reached our Daily users and include…

• Final folder compaction fixes relating to database writes!
• The RSS scrolling fix took a while but has now landed
• Overflow overrides causing scrolling problems are now a thing of the past
• and many more which we listed in release notes for beta.

As usual, if you want to see things as they land, and help us squash some early bugs, you can always check the pushlog and try running daily, which would be immensely helpful for catching things early.

—

Toby Pilling

Senior Manager, Desktop Engineering