I just found out that you could downgrade your 4S from iOS 9.3.5 down to iOS 6.1.3 : r/iphone
Downgrade iPhone 4s to iOS 6.1.3 Using iTunes 2018, Jailbreak, Best Tweaks, iOS 6 Supported Apps - YouTube
Downgrade iPhone 4s from iOS 9.3.6 to iOS 6.1.3 2021 - YouTube
Downgrade iPhone 4s / iPad 2 to iOS 6.1.3 Using 3uTools - 3uTools
Downgrade iPhone 4s / iPad 2 to iOS 6.1.3 Using 3uTools - 3uTools
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Downgrade from iOS 7 to iOS 6.1.3 using iFaith
Downgrade iPhone 4s To iOS 6.1.3 Without Jailbreak Through iTunes (2018) - YouTube
Jailbreak di iOS 6.1.3 con Sn0wbreeze 2.9.14 | Guida by HDblog - HDblog.it
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Downgrading iOS 9.3.5 to iOS 6
You Can Still Officially Downgrade iPhone 4S to iOS 6.1.3 Without Jailbreaking! - YouTube
Downgrade iPhone 4s / iPad 2 to iOS 6.1.3 Using 3uTools - 3uTools
How to officially downgrade your Apple iPhone 4s to iOS 6.1.3
request] [question] unable to activate iPhone 4 (model CDMA 2012) after downgrading to iOS 6.1.3 from 7.1.2 using GeekGrade ipsw. Tried different networks and iTunes but no use.. can somebody please guide
Downgrade iPhone 4s / iPad 2 to iOS 6.1.3 Using 3uTools - 3uTools
Jailbreak di iOS 6.1.3 con Sn0wbreeze 2.9.14 | Guida by HDblog - HDblog.it
Apple stops signing IOS 6.1.3 for iPhone 4S | MacRumors Forums
How to Downgrade iPhone 4 from iOS 7 to iOS 6.1.3 via iFaith [GUIDE] [VIDEO] | IBTimes UK
How to Downgrade iPhone 4s, iPad 2 From iOS 9.3.5 to iOS 6.1.3 and iOS 8.4.1? - 3uTools
How to Downgrade Your iPhone 4S or iPad 2 to iOS 6.1.3 « iOS & iPhone :: Gadget Hacks
How to Downgrade iPhone 4s from iOS 9 to iOS 6.1.3 (Without SHSH Blobs) – iPodHacks142
Downgrade iPhone 4s / iPad 2 to iOS 6.1.3 Using 3uTools - 3uTools