Finished everything on the TODO list (yay!); several CSS cleanups; tons more changes in this commit - see the patch for details
/* This class restores all CSS properties to that absolute positioning of fullscreen mode is correct */
.mceFullscreenPos {
display: block !important;
position: static !important;
left: 0 !important;
top: 0 !important;
bottom: auto !important;
right: auto !important;
width: auto !important;
height: auto !important;
margin: 0 !important;
padding: 0 !important;
border: 0 !important;
overflow: visible;
z-index: 1 !important;
clear: both;
}
body.mceFullscreen {
overflow: hidden !important;
}