All updated configurations are duplicated for the current domain when the "Remember domain selection" option is activated ⚠️

Drupal Version

Drupal 11.1

Domain module version

2.0.x-dev

Expected Behavior

Create domain specific configurations only when the corresponding config form path has been explicitly allowed.

Actual Behavior

We can see that the ConfigFactory doGet method returns a domain specific editable configuration even for configuration like core.extension 😱

Steps to reproduce

Looks like having activated the "Remember domain selection" in the domain configuration UI settings keeps the current selected domain in session and this might cause a few problems as we can see below.

  /**
   * {@inheritdoc}
   */
  protected function doGet($name, $immutable = TRUE) {
    // If config for 'all' domains or immutable then don't override config.
    if (is_null($this->domainConfigUIManager->getSelectedDomainId())) {
      return parent::doGet($name, $immutable);
    }

Once the "Remembered" domain is kept in session we never get into the above code to return without instantiating a domain specific configuration.

  /**
   * {@inheritdoc}
   */
  public function getSelectedDomainId() {
    $id = NULL;

    $request = $this->getRequest();
    if (!is_null($request)) {
      $id = $this->currentRequest->get('domain_config_ui_domain') ?? NULL;
    }
    if (is_null($id) && isset($_SESSION['domain_config_ui_domain'])) {
      $id = $_SESSION['domain_config_ui_domain'];
    }

    return $id;
  }

Every configuration is now being duplicated as a domain specific version when updated as long as we have that domain_config_ui_domain in session.

May be I broke something in some custom personal code, but if so, I haven't found where yet.