Detect blocked popup windows in all browsers

check-for-popup-blocking.js

window.isPopupBlocked = function(popup_window, cb)
{
    var CHROME_CHECK_TIME = 2000;       // the only way to detect this in Chrome is to wait a bit and see if the window is present

    function _is_popup_blocked(popup)
    {
        return !popup.innerHeight;
    }

    if (popup_window) {
        if (popup_window.closed) {
            // opened OK but was closed before we checked
            cb(false);
            return;
        }
        if (/chrome/.test(navigator.userAgent.toLowerCase())) {
            // wait a bit before testing the popup in chrome
            setTimeout(function() {
                cb(_is_popup_blocked(popup_window));
            }, CHROME_CHECK_TIME);
        } else {
            // for other browsers, add an onload event and check after that
            popup_window.onload = function() {
                cb(_is_popup_blocked(popup_window));
            };
        }
    } else {
        cb(true);
    }
};