I prepared my course with Firefox 38. FWIW, in this browser
I observed this behaviour in the console:
|>this.Date.prototype.setTime( 0 )
|<0
|>this.Date.prototype.getTime()
|<0
|>this.Date.prototype.setTime( 1 )
|<1
|>this.Date.prototype.getTime()
|<1
I used this in my course as a simple explanation of setters
and getters. But no. A more recent firefox now gives:
|>this.Date.prototype.setTime( 0 )
|XTypeError: setTime method called on incompatible Object
Well, this was a rather strange way to call rather obscure
functions, so I guess no one will mind anyway.