いや単純にLauncher Hijackって危険なものだからな
中身のコードがどうこうじゃなくてね
Androidにはある仕組みだけど、FireOSでは塞いでる機能を強引に有効化してるわけでな
GitHubのREADMEすら読まずに使ってるっぽいのがの多くて驚いてるが

https://github.com/BaronKiko/LauncherHijack/blob/master/HELP.md
Updates (Specifically 5.6.2.0)
Please disable LauncherHijack in accessibility settings during Fire OS updates.
LauncherHijack causes issues during update 5.6.2.0, you wont brick your device or anything with
it left enabled but you wont be able to complete update 5.6.2.0 until disabled.