This page is aimed at current and future localizers of Thunderbird, Mozilla Messaging's e-mail and usenet client. It covers many aspects a localizer of Thunderbird should be aware of like necessary tools, how to get information about localization-relevant events and various other items of interest.
Creating a Thunderbird localization
Creating a new localization (Mercurial) - This article describes how you can create a new localization for Thunderbird 3.
A localization will added to the l10n dashboard on request when it has reached a high-level of completion (> 80%) as shown by the compare-locales output. To request the addition of your locale to the dashboard, file a bug in the Thunderbird product/Build Config component.
Getting l10n-relevant localization
The Thunderbird l10n coordinator, Simon Paquet, has a blog dedicated to Thunderbird localization, where he regularly posts l10n-relevant news and announcements, that are relevant for the l10n community. You can also subscribe to the blog's RSS feed to be notified once new blogposts are posted to the blog.
Localizers of Thunderbird should the Localization newsgroup (mozilla.dev.l10n) to stay informed of Thunderbird-specific and general l10n-related items of interest to them. They are further encouraged to read the Thunderbird development newsgroup (mozilla.dev.apps.thunderbird) to stay informed of recent Thunderbird-related developments.
Localizers should watch the firstname.lastname@example.org mail address (or its alias :tb-l10n) to stay current on bugs that might affect Thunderbird localizers, especially late in a release cycle. This can be done by adding this mail address to the "User Watching" section of your Email preferences in bugzilla.
A few helpful links
- Open bugs with string impact that have been changed in the last month
- Fixed bugs with string impact that have been changed in the last month
- Open bugs with the l12y (localizability) keyword
- Open bugs which need localizer attention (email@example.com has been CC'ed on that bug)
See the Thunderbird 3 release schedule page.
String freeze impact
After a string freeze of a given, no new English (en-US) strings will be added or changed until the release date. This enables localizers to catch up with all the string changes and give them enough time to translate and test all the l10n-specific changes that were made in the release cycle.
This means that all work for a release that might affect the strings on the UI must be finished before the string freeze date.
Breaking the string freeze
There may be late-breaking changes or security fixes after the string freeze, where the benefit of those changes outweighs the cost of breaking the string freeze. In that case developers will have to do the following:
- Get the string change approved by the relevant driver for the release.
- Add the late-l10n keyword to the relevant bug in 
- Post a note into the localization newsgroup mozilla.dev.l10n or the localization mailinglist firstname.lastname@example.org
- The note should contain a short description of the change and where it is occurring (e.g. in which part of the UI, which dialog, etc.) to enable localizers to adequately test their localization
- The note should also describe possible implications for localizers in case anything special is going on (e.g. the order of the strings is important)
For Thunderbird 3, there are a number of principal locales designated as Tier 1. These are the 10 locales, which are the most important for Thunderbird, because of their number of Thunderbird users or potential for growth.
These locales are being treated as first-class citizens, as important as en-US, which is to say that any Tier 1 locale that does not meet the requirements will block the final release of Thunderbird.
The following are P1 (priority 1) locales in order of priority:
* de - German * fr - French * ja, ja-JP-mac - Japanese * en-GB - British English * es-ES - Spanish (European continent) * it - Italian * pl - Polish * ru - Russian * nl - Dutch * pt-BR - Brazilian Portuguese
All other supported locales are in the tier 2 category.
The locales that are planned to ship with the next end-user release of Thunderbird (currently this is Thunderbird 3) can be found here.