Chrome-only cross-domain scripting errs in Facebook iFrame App upon FB.Login(..)
I also ran into an issue where the getLoginStatus() was not being called in Chrome. I tried calling it on page load and after a user-initiated action with no success.
It turned out that it was not a cross-domain issue. The call was being blocked by the Un-Passwordise extension in Chrome. As soon as I disabled the extension, it worked perfectly, even on page load.
More info about this issue here: FB.getLoginStatus never fires the callback function in Facebook's JavaScript SDK
For my case, it turned out that Chrome complained whenever I called the Facebook JavaScript API's FB.login(..) method immediately upon Page or DOM load.
To circumvent this problem in Chrome I put a button on the page that the user must click to initiate the login script. That works in Chrome. It's a workaround but good enough for me for now.
note: For the secondary page that I mentioned in my question that works, it already was set up for user-initiated login prompt.
Adding a channel file may help this problem. See the Facebook Javascript API documentation:https://developers.facebook.com/docs/reference/javascript/