UserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.116 Safari/537.36

Steps to reproduce the problem:
1. Create document containing empty div with id=HERE
2. Add script;

setTimeout(function() {
    console.log("Reproduction attempt....");
    var mydiv = document.getElementById("HERE");

    console.log(mydiv);
    console.log(typeof(mydiv));

    var otherdiv = document.createElement("div");
    var myshad = mydiv.attachShadow({mode: "open"});
    myshad.innerHTML = '<div id="SHADDIV">Hello</div>';
    var t = myshad.getElementById("SHADDIV");

    console.log(t);
    console.log(typeof(t));
    console.log(Object.keys(t));

    t.appendChild(otherdiv); // errors.
}, 500);

3. Open Console. Load page. 

What is the expected behavior?
No error.

What went wrong?
Uncaught TypeError: Failed to execute 'appendChild' on 'Node': parameter 1 is not of type 'Node'.

Did this work before? N/A 

Chrome version: 53.0.2785.116  Channel: stable
OS Version: OS X 10.11.6
Flash Version: Shockwave Flash 23.0 r0

shadow dom getElementById operations are returning an object with no methods. (Can see this in console log).

This upsets appendChild which wants a Node...