Fix regression from #23271. This code apparently runs on the compare page where there is no review button so check for existance of both button and content. <img width="1226" alt="Screenshot 2023-03-17 at 21 42 47" src="https://user-images.githubusercontent.com/115237/226040001-ec097edd-d926-4c80-9962-526f9b7eff19.png"> Fixes #23562
<div class="button">
<button class="button">