Dialog cannot be dragged properly with IFRAME

Dialog dragging is glitchy when IFRAME is contained within content area. Dialog movement stops when mouse pointer overlaps IFRAME. Same issue occurs when resizing dialog.

The following fix works for me, but I suspect something better could be added into the dialog script.

var __overlay_fix_start = function() {
	var overlay = $(this).find('.hidden-dialog-overlay');
	if (!overlay.length) {
		overlay = $('<div class="hidden-dialog-overlay" style="position:absolute;top:0;left:0;right:0;bottom:0;z-order:100000;"></div>');
		overlay.appendTo(this);
	}
	else
		overlay.show();
};
var __overlay_fix_stop = function() {
	$(this).find('.hidden-dialog-overlay').hide();
};

// Cover dialog content with overlay during resizing / moving
// to avoid unusual results.
options.resizeStart = (options.dragStart = __overlay_fix_start);
// Hide transparent overlay once dragging or resizing has stopped
options.resizeStop = (options.dragStop = __overlay_fix_stop);