pub trait DOMStringMapMethods<D>where
    D: DomTypes,{
    // Required methods
    fn SupportedPropertyNames(&self) -> Vec<DOMString>;
    fn NamedGetter(&self, name: DOMString) -> Option<DOMString>;
    fn NamedSetter(
        &self,
        name: DOMString,
        value: DOMString,
        _can_gc: CanGc,
    ) -> Result<(), Error>;
    fn NamedDeleter(&self, name: DOMString, _can_gc: CanGc);
}