I have 2 windows home.html and result.html.
In home.html I have a #txtinput and a <
In result.html, find the Window which opened it, using window.opener and then take your data of interest from that Window.
window.addEventListener('load', function () { // wait for ready
var home = window.opener, txtinput, txtresult;
if (home) {
txtinput = home.document.getElementById("txtinput");
txtresult = document.getElementById('txtresult');
txtresult.value = txtinput.value;
}
}, false);
In home.html, listen for a click on #btn and open result.html
// assuming button exists at invocation time
var btn = document.getElementById('btn');
btn.addEventListener('click', function () {
window.open('result.html');
}, false);