Note: iOS 12.2+ users who would like to save space may use the Slim version (though this one also works on 12.2 and higher) Supports All devices, iOS 12 — 12.4 Chimera is the first true iOS 12 jailbreak to not only feature a CoreTrust bypass so that binaries don't need to be resigned, but to also support A12 devices, including iPhone Xs, iPhone Xr, and the newest iPads. Chimera doesn't tamper with user files, making it safer than alternatives and includes Sileo, a fully modern package manager designed for iOS 11 and higher!
How to Trust and Open the App
Tap Settings > General > Profiles or Profiles & Device Management. Under the "Enterprise App" heading, you see a profile for the developer.Apple Guide