Running an hta above all windows

I have an HTML application that I want to stay on top of all windows (that is, if another window is opened/switched to, I want this one to cover it). JavaScript solutions don't work in Windows 7/IE9 Mode (not sure which is holding it back, can't change either), and VBScript solutions seem to either fail outright or depend on outside components. I can't use modal dialogs either because I need this to be on top of ALL other windows, not just its parent.

And don't mark this as a duplicate of https://stackoverflow.com/questions/24539339/how-to-open-a-hta-window-on-top-of-all-other-windows because that (unfortunately still unanswered) question refers to opening above other windows, not maintaining stack position.

What I have tried:

• Three of the suggestions outlined here.
• The JavaScript solution here.
• The little VBScript here.
• Probably a dozen or more subtle variations on each of the above.

Keep in mind that I can't download an extra component (no autoit or nircmd). It should all be integrated into a single file, preferably an hta, but not a zip.

My Solution

Only very slightly adapted from Teemu's solution, mainly for portability (just in case).

<script language="javascript">
    var locationstore = location.href
    [...]
    window.onload = function () {
        var shell = new ActiveXObject('WScript.Shell'),
            forceModal = function (e) {
                shell.Run(locationstore, 1, 0);
            };
        top.addEventListener('blur', forceModal, false);
        window.onbeforeunload = function () {
            window.removeEventListener('blur', forceModal, false);
        };
    };
</script>

Here's an evil snippet. It's not perfect, but maybe you can develope it further.

window.onload = function () {
    var shell = new ActiveXObject('WScript.Shell'),
        forceModal = function (e) {
            shell.Run('absolute_path_to_hta', 1, 0);
        };
    top.addEventListener('blur', forceModal, false);
    window.onbeforeunload = function () {
        window.removeEventListener('blur', forceModal, false);
    };
};

WARNING: HTA must run in single instance mode, when testing this snippet.