Notice: Undefined index: settings in panels_edit_configure_access_test_form_submit()

Saving "The front page" visibiliy rule to a pane in a minipanel or panels page variant causes the next notice in db_log:
Notice: Undefined index: settings in panels_edit_configure_access_test_form_submit() (line 2066 of /home/shl/public_html/sites/all/modules/contrib/panels/plugins/display_renderers/panels_renderer_editor.class.php).

Steps to reproduce

1. Start a simplytest.me test width Drupal 7.53 and Panels ( Advanced options -> Add an additional project: Ctools, Panels ).
2. Create a new minipanel or panels page variant.
3. Add some content to last created minipanel or panels page variant.
4. Add "The front page" visibility rule to last created pane.
5. Save the rule ( saving the mini panel or panels page variant is not necessary ).
6. Open /admin/reports/dblog: there is the notice cited above in the log.

The following code shows that $form_state['values']['settings'] does not exist ( /sites/all/modules/panels/plugins/display_renderers/panels_renderer_editor.class.php ).

/**
 * Submit handler for visibility rule settings
 */
function panels_edit_configure_access_test_form_submit(&$form, &$form_state) {
  if (!empty($form_state['clicked_button']['#remove'])) {
    $form_state['remove'] = TRUE;
    return;
  }

  if ($function = ctools_plugin_get_function($form_state['plugin'], 'settings form submit')) {
    $function($form, $form_state);
  }
dsm($form_state['values']);
  $form_state['test']['settings'] = $form_state['values']['settings'];
  if (isset($form_state['values']['context'])) {
    $form_state['test']['context'] = $form_state['values']['context'];
  }
  $form_state['test']['not'] = !empty($form_state['values']['not']);
}

Tested with latest stable and dev version of Panels ( Panels 7.x-3.8 or 7.x-3.x-dev ) with same result.