getDisplayModesLink example

if ($enabled_displays = array_filter($this->getDisplayStatuses())) {
          $default = array_keys(array_intersect_key($display_mode_options, $enabled_displays));
        }
        natcasesort($display_mode_options);
        $form['modes']['display_modes_custom'] = [
          '#type' => 'checkboxes',
          '#title' => $this->t('Use custom display settings for the following @display_context modes', ['@display_context' => $this->displayContext]),
          '#options' => $display_mode_options,
          '#default_value' => $default,
        ];
        // Provide link to manage display modes.         $form['modes']['display_modes_link'] = $this->getDisplayModesLink();
      }
    }

    // In overviews involving nested rows from contributed modules (i.e     // field_group), the 'plugin type' selects can trigger a series of changes     // in child rows. The #ajax behavior is therefore not attached directly to     // the selects, but triggered by the client-side script through a hidden     // #ajax 'Refresh' button. A hidden 'refresh_rows' input tracks the name of     // affected rows.     $form['refresh_rows'] = ['#type' => 'hidden'];
    $form['refresh'] = [