This is the only workaround I've found so far:

// MooTools
window.addEvent('domready',function() {

    Element.prototype.hide = function() {
        alert('Intercepted');
        // Do nothing
    };
});

This is the only workaround I've found so far (opened for review):

// MooTools
window.addEvent('domready',function() {

    Element.prototype.hide = function() {
        alert('Intercepted');
        // Do nothing
    };
});