OO.ui.ProcessDialog and other dialogs should be draggable and resizable just like the File -> Save dialogs are in any web browser. Things like

OO.inheritClass( ProcessDialog, OO.ui.ProcessDialog );
var processDialog = new ProcessDialog({
    size: 'large',
    escapable: 'true',
    draggable: true,
    resizable: true
});

should work. jQuery does it here: http://jqueryui.com/dialog/#modal Maybe I am mistaken and we already can do this using a CSS rule or something else, but I do not know of it.