Howto: Modify block format options dropdown in WordPress (TinyMCE)

There is an easy way to modify the block format options dropdown in the WordPress editor. Simply add those lines to your theme’s functions.php (wp-content/themes/{name}/functions.php) and modify the list according to your needs:

function extend_tiny_mce_defaults ($config) {
  // comma separated list of any block-level HTML tag 
  $config['theme_advanced_blockformats'] = 'p,h3,h4,pre,address'; 
  return $config;
}

add_filter('tiny_mce_before_init', 'extend_tiny_mce_defaults', 100);