Globals can define a named property setter

[annevk]

Window does and IDL even defines how it's handled (creates a separate prototype object).

https://heycam.github.io/webidl/#Global suggests they can't: "The interface must not define a named property setter."

[annevk]

We should probably disallow it for any new globals though. E.g., globals defined in 2016 or later. 😛

[bzbarsky]

I think you confused getter and setter here. Window has a named property getter.

[annevk]

I did, thanks!