@namespace url(http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul);

/* ::::: lines connecting cells ::::: */
treechildren::-moz-tree-line {
  visibility: visible !important;
}

/* The following two rules were copied from FF 2.0 and are required as well */
treechildren::-moz-tree-line {
  border: 1px dotted ThreeDShadow;
}
treechildren::-moz-tree-line(selected, focus) {
  border: 1px dotted HighlightText;
}