8 – Private Message Module: Editing “Send private message” Link to include Username

I prefer to edit (hack) the private message module directly in this case if you won’t mind helping me. https://www.drupal.org/project/private_message 8.x-2.0-beta16

I want to change the message from 'Send private message' to 'Send private message to @username' which should display the username from the user’s page that we are visiting and contacting.

The module has the following t()-function saying:

'#title' => t('Send private message'),

Is there are way to hack this line directly to insert the username. I tried myself a number of ways, but failed.

The relevant code is located in: private_messagesrcServicePrivateMessageService.php#L336-382

  public function createRenderablePrivateMessageThreadLink(array &$build, EntityInterface $entity, EntityViewDisplayInterface $display, $view_mode) {
    if ($display->getComponent('private_message_link')) {
      if ($entity instanceof UserInterface) {
        $author = $entity;
      }
      else {
        $author = $entity->getOwner();
      }
      $current_user = Drupal::currentUser();
      if ($current_user->isAuthenticated()) {
        if ($current_user->hasPermission('use private messaging system') && $current_user->id() != $author->id()) {
          $members = ($current_user, $author);
          $thread_id = $this->mapper->getThreadIdForMembers($members);
          if ($thread_id) {
            $url = Url::fromRoute('entity.private_message_thread.canonical',
('private_message_thread' => $thread_id), ('attributes' => ('class' =>
('private_message_link'))));
            $build('private_message_link') = (
              '#type' => 'link',
              '#url' => $url,
              '#title' => t('Send private message'),
              '#prefix' => '<div class="private_message_link_wrapper">',
              '#suffix' => '</div>',
            );
          }
          else {
            $url = Url::fromRoute('private_message.private_message_create', (), ('query'
=> ('recipient' => $author->id())));
            $build('private_message_link') = (
              '#type' => 'link',
              '#url' => $url,
              '#title' => t('Send private message'),
              '#prefix' => '<div class="private_message_link_wrapper">',
              '#suffix' => '</div>',
            );
          }
        }
      }
      else {
        $url = Url::fromRoute('user.login');
        $build('private_message_link') = (
          '#type' => 'link',
          '#url' => $url,
          '#title' => t('Send private message'),
          '#prefix' => '<div class="private_message_link_wrapper">',
          '#suffix' => '</div>',
        );
      }
    }   
  }

Thanks very much for your help.