So I was notified this past Friday that the JavaScript on our IDX solution was broken in IE 6, but only when it was being framed by one of our customers on their website. Weird, but I figured I must have busted something from my deploy earlier that day. After jumping into the problem, I realized that the issue wasn’t actually with my code but rather, believe it or not, with Google’s AJAX search API. Specifically, the issue that I found was that IE 6 absolutely will not execute JavaScript under the following conditions:
1) The visitor is using IE 6 to visit a page.
2) That page frames another page that requests JavaScript.
3) The JavaScript is served with HTTP headers that specifically include the “no-cache” command in the “Cache-control” headers; other, similar headers (such as “private”, “no-store”, etc) do not have the same effect.
4) The JavaScript is GZIP’d.
I figured that Google must have either recently added the no-cache header or recently started gzip-ing, so I posted the problem in Google Groups. Today, they made a post notifying me (and everyone else) that they fixed the problem. Sure enough, I fired up Fiddler just now, and it seems that they no longer gzip the response when serving up their www.google.com/jsapi application.
Anyway, I had encountered this problem before, but I just chalked it up to something that everyone else probably already knew. As it turns out, a Google search turns up absolutely nothing on this issue. Since I couldn’t find anything, I figured that the world would benefit from this knowledge.
