This is the gold standard. You need to uninstall your modern iTunes COMPLETELY and install iTunes 11.0.5.
For users looking to relive the golden age of iOS 6 jailbreaks, is the go-to tool. Developed by the legendary @winocm, @iH8sn0w, and @SquiffyPwn, it remains the only tool capable of jailbreaking iOS 6.1.3 through 6.1.6 untethered on devices like the iPhone 4S, iPhone 5, and iPad 4. p0sixspwn requires itunes 105 or above 2021
The application logic for checking iTunesVersion has been updated to support version numbers 12.10+ and 12.11+ (2020-2021 releases). This is the gold standard
If the device is still not detected after the software downgrade: p0sixspwn requires itunes 105 or above 2021