System

Uses the platform's native user-dictionary mechanism, which persists across app restarts. Scope of that persistence varies:

• iOS / macOS: OS-wide (shared with every app on the device).

• Windows: per-user, per-language Windows dictionary.

• Linux (Hunspell): per-user file at ~/.local/share/hunspell/{lang}_user.dic.

• Android: no native API exists; falls back to AppLocal with a warning.

Removal support is best-effort and not available everywhere (e.g. Windows basic ISpellChecker does not expose remove).