Drupal 7 dashboard doesn't fit on screen when using custom themes

Question

I'm using Drupal 7 for a site I'm making, but when I am using the dashboard/backend of drupal the modal box doesn't fit on my screen and causes a wierd scrollbar (FF & Chrome etc) bug that I've never seen before on any site!

See how the bottom down arrow has disappeared?

On some screens this means that I can't see the bottom of the page, hiding the save buttons.

It works fine with drupal standard themes, but not on my Zen subtheme.

Has anyone seen this before? or has anyone got a theory on how to fix this?

Thanks in advance.

Answer 1

You can get rid of the overlay completely by disabling the Overlay module.