@Nullable
    @Override
    public String getToolTipText(@NotNull DBNNode node, @NotNull Tree tree, @NotNull Event event) {
        return null;
    }
Default node renderer.
Draws connection type marker next to the item name.
plugins/org.jkiss.dbeaver.ui.navigator/src/org/jkiss/dbeaver/ui/navigator/database/DefaultNavigatorNodeRenderer.java