Monterey Preview- Blank figures in manuscript PDFs

I’ve noticed blank figures in several journal manuscript PDFs. So far, I’ve found these defects in two 2006 and 2007 PDFs from the Proceedings of the National Academy of Sciences, and in a 2012 PDF from Science. In the latter case, the missing figure is perfect when the onliine PDF is viewed in Safari. Not all figures are missing- just one to three per manuscript. These were perfect when viewed in Preview from all previous Mac OSs prior to Monterey. My alternative is to view in an Adobe product, where they’re fine. My version of Preview is 11.0 (1003.4).
Has anyone else noted these issues? I’ve been working with a contact from Apple, but I fear this hasn’t gotten much notice since I’m apparently the first to bring this to their attention.