A window management issue was addressed with improved state management. This issue is fixed in Safari 17, iOS 17 and iPadOS 17, watchOS 10, macOS Sonoma 14. Visiting a website that frames malicious content may lead to UI spoofing.
https://support.apple.com/en-us/HT213941
https://support.apple.com/en-us/HT213940
https://support.apple.com/en-us/HT213938
https://support.apple.com/en-us/HT213937
http://seclists.org/fulldisclosure/2023/Oct/9
http://seclists.org/fulldisclosure/2023/Oct/8