I looked in the ui.sortable.js file and found that the call to it was commented out on line 186 (in my file). When I uncommented it, errors spewed (prob why it was commented).

After playing with it for a couple hours, I think I fixed it by commented out the $(self.helper).remove(); line (178).

All seems to work now in FF.

Hope this helps....

I will attach the source for a diff....

The current code for positioning a dialog window does not work if the dialog source DIV is 'hidden', which is likely to be a common way of using the dialog component. (I put my dialogs inside a hidden container div.) The problem is that you cannot 'measure' a div that is not displayed. This prevents the proper positioning of the dialog, such as 'center'.

There is a very simple solution - set...

display: block; visibility: hidden

...before measuring width and height. This allows dimensions to be taken without making the DIV visible.

Here is the modified 'open' code - only the first and last lines are new...

this.open = function() {
  uiDialog.appendTo('body')'''.css({ visibility: 'hidden' })'''.show();
  var wnd = $(window), top = 0, left = 0;
  switch (options.position) {
    case 'center':
      top = (wnd.height() / 2) - (uiDialog.height() / 2);
      left = (wnd.width() / 2) - (uiDialog.width() / 2);
      break;
    case 'left':
      top = (wnd.height() / 2) - (uiDialog.height() / 2);
      left = 0;
      break;
    case 'top':
      top = 0;
      left = (wnd.width() / 2) - (uiDialog.width() / 2);
      break;
  }
  uiDialog.css({ top: top, left: left, visibility: 'visible'  });
};

The datepicker (v3.0) does not position itself so it is always visible to users.

Ideally, information about the user's browser window, the desired launch position, and the size of the calendar could be used to position the calendar such that it is always visible.