Localization with String Catalogs
Essence
A String Catalog (Localizable.xcstrings, Xcode 15+) is a single file with all strings and translations instead of a pair of .strings and .stringsdict files per language. At build time Xcode finds strings in the code, adds them to the catalog and shows the state of every translation. Inside it's JSON, and compiled .strings and .stringsdict files end up in the bundle.
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