Open TinyMCE editor second row by default

TinyMCE editor used in WordPress usually has two rows on its toolbar. But, the second row is hidden by default, and you need to click an icon on first toolbar row to open the second row.

If you want this second row to be open by default, here is a small piece of code to do that and it will affect every TinyMCE you have on your website:

function dev4press_tiny_mce_before_init($args) {
  $args['wordpress_adv_hidden'] = false;

  return $args;
}

add_filter('tiny_mce_before_init', 'dev4press_tiny_mce_before_init');

You can add this code in theme functions.php file.