mozilla/gecko-dev
Localization
Firefox ships in 100+ locales. Strings live in two formats: classic .properties / .dtd files (legacy) and Fluent .ftl files (modern).
Fluent
Fluent is Mozilla's localization system, designed for natural-language nuances (genders, plurals, lookups, terms). The runtime lives in intl/l10n/, with bindings under dom/l10n/ and toolkit/components/mozintl/.
A snippet:
hello = Hello, {$name}!
welcome = Welcome to { -brand-short-name }.Localizers translate .ftl files in separate l10n repositories (one per locale, e.g. mozilla-l10n/firefox-l10n); CI assembles the localized builds.
Where strings live in this tree
<app>/locales/en-US/**/*.ftl— English source (e.g.,browser/locales/en-US/).<app>/locales-preview/— preview / experimental strings.dom/locales/,toolkit/locales/,mobile/locales/— per-app source strings.
ICU and i18n
intl/ contains internationalization utilities (segmenter, locale matching, lookup) plus a vendored copy of ICU.
Related
Built by Factory AutoWiki from public repository content. It is a generated preview for codebase exploration, not source-maintained documentation.