Give me my HTML in my Drupal 8 menu links!

theming-hell.php

<?php 

/**
 * Implements hook_preprocess_menu().
 */
function THEME_preprocess_menu(&$vars, $hook) {
  if ($hook == 'menu__account') {
    $items = $vars['items'];
    foreach ($items as $key => $item) {
      if ($key == 'user.page') {
        $vars['items'][$key]['title'] = array(
          '#markup' => 'Log the <i>fuck</i> in!',
          '#allowed_tags' => array('i'),
        );
      }
      if ($key == 'user.logout') {
        $vars['items'][$key]['title'] = array(
          '#markup' => 'Log the <i>fuck</i> out!',
          '#allowed_tags' => array('i'),
        );
      }
    }
  }
}