The hardcoded English keyword(s) for this gambit, used as a canonical
alias so that English always works regardless of the active locale.
Defaults to key(), which is correct when the gambit is not translated.
Override this in subclasses that translate key() via the translator.
Returns string
filterKey
filterKey():string
This is the server standardised filter key for this gambit.
The filter key must not be localized.
The hardcoded English keyword(s) for this gambit, used as a canonical alias so that English always works regardless of the active locale. Defaults to key(), which is correct when the gambit is not translated. Override this in subclasses that translate key() via the translator.