Bug 54737 Libraries dialog doesn't remember status of items in library tree
Preferences > Java > Build Path > User Libraries: The dialog does not seem to correctly remember the status of the items in the "Defined user libraries" tree. When I leave the dialog I close (un-cascade) all items. When I open the dialog again, most of the items are open (cascaded) again. This is disturbing because I cannot overview the items. It's like opening the Windows explorer with not only the drives shown but all folders being open.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/dialogfields/TreeListDialogField.java
fButtonControls= new Button[fButtonLabels.length];
				for (int i= 0; i < fButtonLabels.length; i++) {
					String currLabel= fButtonLabels[i];
					if (currLabel != null) {
						fButtonControls[i]= createButton(contents, currLabel, listener);
						fButtonControls[i].setEnabled(isEnabled() && fButtonsEnabled[i]);
					} else {
						fButtonControls[i]= null;
						createSeparator(contents);
					}
				}
			}
			fLastSeparator= createSeparator(contents);
			updateButtonState();
			fButtonsControl= contents;
		}
		return fButtonsControl;
	}
	private void doButtonSelected(SelectionEvent e) {
		if (fButtonControls != null) {
			for (int i= 0; i < fButtonControls.length; i++) {
				if (e.widget == fButtonControls[i]) {
					buttonPressed(i);
					return;
				}
			}
		}
	}
	/**
	* Handles key events in the table viewer. Specifically