Question: I have googled as much as I can and I'm not sure of the support for the document of an iframe getting the id of itself in the parent window: `window.frameElement.id`. There are so many browsers that it's hard to test them all and nothing online seems to have any information. I'm specifically wondering about:

Safari
iOS Safari
Windows Phone IE
IE 7, 8, 9, 10, 11

(I tested Firefox and Chrome and they both worked).

**EXAMPLE IFRAME CONTENT**

```
<!DOCTYPE HTML>
<html>
    <head></head>
<body>
        <script type="text/javascript">
            var owner = window.frameElement;
            var thisIsWhoIsCalling = ( owner !== null ) ? owner.id : null;
            window.parent.SomeJavaScriptObject.someFunction( thisIsWhoIsCalling );
        </script>
    </body>
</html>

```

Answer: 
I happened to look for the same information.
Here's what I have found.

<https://developer.mozilla.org/en-US/docs/Web/API/Window.frameElement>

I have tested some browsers in addition to the MDN doc, and confirmed that it is supported by IE7+, Safari, Firefox, Chrome. So pretty much all browsers.

I haven't tested on IE6-, but I guess you don't need to care.
```
var frame = window.frameElement;  //Get <iframe> element of the window
if (frame) { window.location.href = "/403.shtml"; ...

```

This code not working for me in cross browser (FF,Chrome,IE)
A prefer this one, working ok and cross browser...

```
  if (window.self === window.top) window.location.href = "/403.shtml";
//or if (window.self !== window.top) window.location.href = "/403.shtml";

```