Same issue, was doing an empty() check on $page_urlname in Admin:PageManager and not taking both main pages into account
/* CSS file for cell dialog in the table plugin */
.panel_wrapper div.current {
height: 200px;
}
.advfield {
width: 200px;
}
#action {
margin-bottom: 3px;
}
#class {
width: 150px;
}