This issue seems to be related to how the new Sequoia update manages window layering. A workaround that might help is to try resetting your app preferences. Close the Photos app, then open Finder and go to "Go" > "Go to Folder" and type `~/Library/Preferences/`. Find the preference file related to Photos, like `com.apple.Photos.plist`, and move it to your desktop. Restart your Mac and open Photos again to see if the issue persists. If this doesn't work, you may want to report this behavior to Apple, as it could be a bug that needs addressing in a future update.