private void registerSelectItemAction() {
    int[] allowedModifiers = new int[]{
      0,
      InputEvent.SHIFT_MASK,
      InputEvent.CTRL_MASK,
      InputEvent.META_MASK,
      InputEvent.ALT_MASK
    };

    ShortcutSet selectShortcuts = ActionManager.getInstance().getAction(SearchEverywhereActions.SELECT_ITEM).getShortcutSet();
    Collection<KeyboardShortcut> keyboardShortcuts = ContainerUtil.filterIsInstance(selectShortcuts.getShortcuts(), KeyboardShortcut.class);

    for (int modifiers : allowedModifiers) {
      Collection<Shortcut> newShortcuts = new ArrayList<>();
      for (KeyboardShortcut shortcut : keyboardShortcuts) {
        boolean hasSecondStroke = shortcut.getSecondKeyStroke() != null;
        KeyStroke originalStroke = hasSecondStroke ? shortcut.getSecondKeyStroke() : shortcut.getFirstKeyStroke();

        if ((originalStroke.getModifiers() & modifiers) != 0) continue;

        KeyStroke newStroke = KeyStroke.getKeyStroke(originalStroke.getKeyCode(), originalStroke.getModifiers() | modifiers);
        newShortcuts.add(hasSecondStroke
                         ? new KeyboardShortcut(shortcut.getFirstKeyStroke(), newStroke)
                         : new KeyboardShortcut(newStroke, null));
      }
      if (newShortcuts.isEmpty()) continue;

      ShortcutSet newShortcutSet = new CustomShortcutSet(newShortcuts.toArray(Shortcut.EMPTY_ARRAY));
      DumbAwareAction.create(event -> {
        int[] indices = myResultsList.getSelectedIndices();
        elementsSelected(indices, modifiers);
      }).registerCustomShortcutSet(newShortcutSet, this, this);
    }
  }
private void registerSelectItemAction()