private static void patchGtkDefaults(UIDefaults defaults) {
    if (!UIUtil.isUnderGTKLookAndFeel()) return;

    Map<String, Icon> map =
        ContainerUtil.newHashMap(
            Arrays.asList(
                "OptionPane.errorIcon",
                "OptionPane.informationIcon",
                "OptionPane.warningIcon",
                "OptionPane.questionIcon"),
            Arrays.asList(
                AllIcons.General.ErrorDialog,
                AllIcons.General.InformationDialog,
                AllIcons.General.WarningDialog,
                AllIcons.General.QuestionDialog));
    // GTK+ L&F keeps icons hidden in style
    SynthStyle style = SynthLookAndFeel.getStyle(new JOptionPane(""), Region.DESKTOP_ICON);
    for (String key : map.keySet()) {
      if (defaults.get(key) != null) continue;

      Object icon = style == null ? null : style.get(null, key);
      defaults.put(key, icon instanceof Icon ? icon : map.get(key));
    }

    Color fg = defaults.getColor("Label.foreground");
    Color bg = defaults.getColor("Label.background");
    if (fg != null && bg != null) {
      defaults.put("Label.disabledForeground", UIUtil.mix(fg, bg, 0.5));
    }
  }