_keepAnOriginalSettingsCopy() {
        this.originalDigitGroupSeparator = this.settings.digitGroupSeparator;
        this.originalCurrencySymbol      = this.settings.currencySymbol;
        this.originalSuffixText          = this.settings.suffixText;
    }
Original settings saved for use when the `decimalPlacesShownOnFocus` and `showOnlyNumbersOnFocus` options are used.
Those original settings are used exclusively in the `focusin` and `focusout` event handlers.