docs: private HashSet<LabelAtom> getDynamicLabels() {
          HashSet<LabelAtom> result = new HashSet<LabelAtom>();
          for (LabelFinder labeler : LabelFinder.all()) {
              // Filter out any bad(null) results from plugins
              // for compatibility reasons, findLabels may return LabelExpression and not atom.
              for (Label label : labeler.findLabels(this))
                  if (label instanceof LabelAtom) result.add((LabelAtom)label);
          }
          return result;
      }