The arity property used to return the number of arguments expected by the function, however, it no longer exists and has been replaced by the Function.prototype.length property.
The Intl.NumberFormat.prototype.format property returns a getter function that formats a number according to the locale and formatting options of this NumberFormat object.
The __noSuchMethod__ property used to reference a function to be executed when a non-existent method is called on an object, but this function is no longer available.
The Symbol.hasInstance well-known symbol is used to determine if a constructor object recognizes an object as its instance. The instanceof operator behavior can be customized by this symbol.