ADR 0185: Korean shell locale

• Status: Accepted
• Date: 2026-09-09
• Decision owners: PI-Desktop desktop/i18n maintainers
• Related: ADR 0160, ADR 0182, ADR 0183, D349, E2E-091

Context

The searchable locale registry already supports complete shell catalogs, but Korean users were still limited to English or another shipped locale. Korean is a distinct language and should not be represented by an English fallback or by a Chinese catalog with a Korean label.

Decision

1. Ship a complete Korean shell catalog at packages/i18n/src/locales/ko, with native name 한국어 and English name Korean.
2. Resolve ko and regional ko-* OS locale tags to the Korean catalog. Add ko to persisted AppSettings.language and to the Electron Chromium locale allowlist.
3. Ship a Korean product changelog catalog with the same stable version and highlight-count set as English so release notes follow the active shell locale.
4. Preserve the existing English-first catalog contract: identical keys, interpolation variables, searchable picker behavior, and English fallback for plugin-contributed labels. No host protocol, storage schema, or IPC version changes.

Consequences

• Korean users can select Korean or use Auto detection without reloading the renderer.
• Catalog and changelog parity tests cover Korean alongside the existing shipped locales.
• Regional Korean variants intentionally share one base catalog; spelling differences can be added later without changing the picker contract.

Alternatives

• Register ko while falling back to English: rejected because the picker would advertise an untranslated shell.
• Add region-specific Korean catalogs immediately: rejected because the current locale contract uses one maintainable catalog per language.