In Photos app RAW files turn grey after editing

The RAW files imported to the Photos app on my 2019 MacBook Air completely grey out after editing, in most instances. They reappear if I 'revert to original'. I have read that Photos is designed to support RAW files so I'm hoping someone can help me solve the issue please. The RAW files show as .ARW in the Photos app. I've tried to upload a screen shot but not having any luck.