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I have noticed the same kind of things for a number of applications, not just Photos. I suspect there is a system wide setting to change, but have not found yet.
 
Lately when I click an icon on the dock to launch an app., it opens behind my current active window on my M4Pro Mac Mini. So just now, viewing this forum page in Safari, I clicked on Photos and the window opened behind my Safari window.

I'd be interesting to learn how to deselect this new 'feature.'
 
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.
 
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