Apple News
Saurik Updates Substrate Safe Mode to Fix Issues with the iOS 10 Yalu Jailbreak
The new update, which comes with the build number 0.9.6000, is available right now from Cydia’s Changes tab after refreshing your sources, so long as you haven’t already updated it yet.
The restart option now works fine with the latest version of the Yalu jailbreak such as beta 6 and beta 7 for iOS 10.2. There’s still an issue with the older Yalu jailbreak for iOS 10 – iOS 10.1.1 where the restart option causes your device to “lock up” and force you to reboot manually. This is a known issue and we’re yet to see a fix that solves the problem.
When you install a faulty or incompatible tweak, your device will crash and go into Safe Mode rather than causing any critical issues. When in safe mode mode, all the installed jailbreak tweaks are disabled to allow you to safely remove the faulty tweak and go back to stable mode.
Have you update Cydia Substrate or not ?