svoid conceptLanguageToolTips() {
  thread "conceptLanguageToolTips" {
    repeat with ms sleep 500 {
      Component c = componentAtMouse();
      if (c instanceof JComponent) {
        S word = wordAtMouse(), msg = "";
        if (possibleGlobalID(word)) {
          aiConceptsMap_clearCache(60); // clear cache every 60 seconds
          S name = conceptToName(word);
          if (neq(name, word))
            msg = word + ": " + name;
        }
        setToolTipText((JComponent) c, msg);
      }
    }
  }
}