public function getRevisionById($revisionId)
    {
        $revision = $this->revisions->get($revisionId);

        if ($revision !== null) {
            return $revision; //We get here when rendering an unpublished page version
        }

        foreach ($this->revisions as $revision) {
            if ($revision->getRevisionId() === $revisionId) {
                return $revision; //We get here when publishing a new page version
            }
        }

        return null;
    }