Issue #3252865 by Taran2L, svenryen, Karol Haltenberger: Config is missing...

    $text_color = ($jquery_colorpicker_version === 2) ? substr($form_state->getValue('popup_text_hex'), 1) : $form_state->getValue('popup_text_hex');

    // Save settings.

    $this->config('eu_cookie_compliance.settings')

    $config = $this->config('eu_cookie_compliance.settings');

    $config

      ->set('cookie_policy_version', $form_state->getValue('cookie_policy_version'))

      ->set('domain', $form_state->getValue('domain'))

      ->set('popup_enabled', $form_state->getValue('popup_enabled'))

      ->set('accept_all_categories_button_label', $form_state->getValue('accept_all_categories_button_label'))

      ->set('containing_element', $form_state->getValue('containing_element'))

      ->set('settings_tab_enabled', $form_state->getValue('settings_tab_enabled'))

      ->set('accessibility_focus', $form_state->getValue('accessibility_focus'))

      ->save();

      ->set('accessibility_focus', $form_state->getValue('accessibility_focus'));

    // Manually add dependencies on filter formats.

    $dependencies = [];

    $text_format_keys = [

      'mobile_popup_info',

      'popup_agreed',

      'popup_info',

      'withdraw_message',

    ];

    foreach ($text_format_keys as $key) {

      $dependencies[] = 'filter.format.' . ($form_state->getValue($key)['format'] ?? filter_default_format());

    }

    $config->set('dependencies', [

      'config' => array_unique($dependencies),

    ]);

    $config->save();

    parent::submitForm($form, $form_state);

  }