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+### Multilingual Support in QuickLook
+
+**QuickLook Core Application (QL Main Program):**
+
+- QuickLook implements multilingual support using separate XML files for each supported language.
+- All UI strings, messages, and text displayed by QuickLook are stored in these XML language files.
+- When adding a new feature, all supported language files must be updated; every string key must be translated in every language’s XML. Missing translations are not allowed.
+- On startup, QuickLook loads the language file corresponding to the user’s system locale, ensuring a consistent and complete localized UI.
+
+**QuickLook Plugins:**
+
+- Plugins also implement localization using XML language files, following the same structure and requirements as the main program.
+- Each plugin must maintain its own language files for every supported language, covering all displayed UI strings and messages.
+- Any addition of new strings or features in a plugin requires translating every string into all supported languages and updating the XML files accordingly.
+- The plugin loads the appropriate XML language file at runtime based on the system or QuickLook's selected language.
+
+**Important Note:**
+When implementing or updating multilingual support in QuickLook or its plugins, **all supported languages must be present and fully localized in the XML files**. Partial or missing translations are not permitted.
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