New features through add-ons

Havi Hoffman

Until recently, development of new features in Thunderbird used a development style where initial versions created by a developer and designer would “land” in the the Thunderbird nightly releases and evolve based on feedback from those users.

Experience has showed us that while nightly users are very helpful in detecting unexpected bugs that show up unexpectedly, that nightly builds are not a great way to develop new user interface features. First, people using Thunderbird nightlies aren’t always interested in that specific feature, so any raw intermediate state makes their daily email experience less pleasant; second, there’s no commonly known mechanism for feedback on a specific feature, so while we may have many users, they often don’t know how to do anything except “file a bug”, which is great for bugs, but not great for user experience feedback; finally, we can only get feedback from people who are brave enough to try out builds that are not tested, which is a very non-representative population sample!

With the Quick Filter feature, we tried something different.

Right from the start, Quick Filter started out as an optional add-on to Thunderbird which was available to anyone running Thunderbird 3.0 or better. We used blogs, bugs, and an page on the Add-ons website to publicize and solicit feedback about the release of the add-on to a much better targeted audience.  We got lots of high quality feedback quickly, were able to create new revisions quickly, and generally made much faster progress.

After incorporating much of the feedback into the add-on the Thunderbird team felt it was ready to put into Thunderbird for everyone to use.  Only then did we take on some of the tasks that are required for production software (extensive unit tests, better code documentation, etc.).  By separating the iterative, user experience-focused and feedback-gathering phase from the hardening phase, we were able to get to a highly usable, stable feature much faster.

The Quick Filter add-on is therefore the first of our “graduate” add-ons.  With this blog, we’re expanding from the process that we started with Quick Filter, and making it easier for more interested testers to get involved.