window.top === window false condition in IE8

Question

For some reason, using the

window.top === window

condition in IE8 always evaluates to false (in other browsers it works fine). What is the reason for this, and is there any other way for this condition to work cross-browser?

Thanks,

Joel

Answer 1

It's a very complicated topic, but the short version is, use == when comparing windows, not ===, because of the "internal" vs. "external" reference aspect of it. You'll find that (for instance) window === self is false on some browsers.