static JLabel showSuggestion_current;
sbool showSuggestion_keyListenerInstalled;

// action is called in new thread
static JLabel showSuggestion(fS suggestionText, fO action) {
  hideSuggestion();
  final int fontSize = 20, buttonFontSize = 15;
  final JLabel label = fontSize(fontSize, jCenteredMultiLineLabel(suggestionText));
  final VF1<JFrame> framePost = getThreadLocal(makeFrame_post);
  swing {
    makeFrame_post.set(or(framePost, vf1_frameAutoRequestFocusFalse()));
    JFrame f = alwaysOnTop(showPackedFrameInBottomRightCorner(
      withLineBorder(Color.black, withMargin(
        centerAndSouth(
          label,
          withTopMargin(makeFirstButtonBold(fontSizeAll(buttonFontSize, jcenteredbuttons(
            "OK" + appendBracketed(hotKey_teach()), r {
              hideSuggestion(label);
              callFInNewThread(action);
            }, "No", r { hideSuggestion(label) })))))))));
    disposeWindowAfter_unlessMouseInIt(f, 3.0);
    showSuggestion_current = label;
    
    showSuggestion_installHotkey();
  }
  ret label;
}

svoid showSuggestion_installHotkey {
  if (showSuggestion_keyListenerInstalled) ret;
  showSuggestion_keyListenerInstalled = true;
  onGlobalHotKey(hotKey_teach(), r-awt {
    if (isComponentShowing(showSuggestion_current))
      clickFirstButton(getWindow(showSuggestion_current));
  });
}