public function getDifference()
{
$history = PostsHistory::findLast($this);
if (!$history->valid()) {
return false;
}
if ($history->count() > 1) {
$history = $history->offsetGet(1);
} else {
$history = $history->getFirst();
}
/** @var PostsHistory $history */
$b = explode("\n", $history->content);
$diff = new Diff($b, explode("\n", $this->content), []);
$difference = $diff->render(new SideBySide());
return $difference;
}