Block build output, theme and allowed_tags tags

Thu, 04/23/2020

To output block, you can attach which theme template will output it, which library to attach to it, what markup will be outputed and in the end what tags can be in this markup
 

  public function build() {
    $build = [];
    $build['#theme'] = 'custom_block';
    $build['#attached'] = array('library' => array('my_module/library_name'));
    $build['custom_block']['#markup'] = '<div id="totle-widget"></div>';
    $build['custom_block']['#allowed_tags'] = ['div','script'];
    
    return $build;
  }