$chapter = $this->queries->chapters->findVisibleBySlugsOrFail($bookSlug, $chapterSlug);
$this->checkOwnablePermission('restrictions-manage', $chapter);
$chapter = $this->queries->chapters->findVisibleBySlugsOrFail($bookSlug, $chapterSlug);
$this->checkOwnablePermission('restrictions-manage', $chapter);