Insert a js on head of cross-domain iframe content

Question

my problem is: I have some tabs with a dropdown menu,each tab has an iframe:

When the user clicks the dropdown menu I need to run some js on iframe content,then I thought that the correct thing to do is this js in my html page:

    var scriptTag = "<script>alert("blabla");<"; // saving script to run
    scriptTag += "/script>"; //add this for fixing the script tag problem
    $("#myframeid").contents().find("head").append(scriptTag); //appending the script on the head of iframe

But when I run it, the console reports like:

Uncaught SecurityError: Failed to read the 'contentDocument' property from 'HTMLIFrameElement': Blocked a frame with origin " http://localhost:8080 " from accessing a frame with origin " http://www.otherdomainsite.com ". Protocols, domains, and ports must match.

Obviously if it is on a different domain it does not run,so what I have to do now? Am I doing something wrong?

I heard about postMessage ecc.. methods but I never used them.

Thank you in advance.

Answer 1

You are not allowed to execute code against an external domain IFRAME.

The only way, would be to have proxy iFrame for each direction of message passing.

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