}
private void initializeToolbars(Composite parent) {
ToolBarManager tbm = CompareViewerPane.getToolBarManager(parent);
if (tbm != null) {
tbm.removeAll();
// define groups
tbm.add(new Separator("modes")); //$NON-NLS-1$
tbm.add(new Separator("merge")); //$NON-NLS-1$
tbm.add(new Separator("navigation")); //$NON-NLS-1$