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GitHub - grappler/i18n: i18n WordPress tools
Localization | Common APIs Handbook | WordPress Developer Resources
How to Change Language Strings in WordPress
Make your WordPress theme or plugin translation-ready | WPtorium
How to localize your WordPress themes and plugins | WPastronaut
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Creating a WordPress Multilingual Site — Part 2: Beginning Custom Theme Localization with gettext | by Phrase | i18n and l10n Resources for Developers | Medium
Translating Your WordPress Themes and Plugins | ractoon
ease inheritance in order to support Twig/Timber · Issue #52 · wp-cli/i18n- command · GitHub