This stackoverflow question made me look into how localStorage is defined and there is a point that seems weird. As I read it, each Document has its local storage holder set only when the localStorage getter is called, and the broadcast operation fires event only on globals that have a matching Storage holder. So if a Document does set a storage event listener without calling that getter it wouldn't receive events? All browsers seem to fire it anyway https://jsfiddle.net/yspr304z/ So why define it only in the getter? Did I miss something or should I open an issue?