iOS hacker Jake James has released rootlessJB 3.0 and it is now available for download. The jailbreak that supports iOS 12.0 up to iOS 12.1.2 works on devices that have A9, A10 and A11 chips. Sadly A12 devices such as iPhone XS are not supported yet.
The rootlessJB jailbreak is a developer focused release and currently does not allow tweaks or code injections, however this could change in the future. In its current state the jailbreak is able to spawn SSH via Dropbear.
As this is a rootless jailbreak it does not require a remount and will not install Cydia. When using this type of jailbreak, iOS users can install customizations to their device using SSH. The hacker has also noted that users will be able to sign tweaks using a legitimate certificate that you can acquire by signing up for free Apple developer account.
Regarding support for A12 devices James said that support for these devices will be added soon. Support for older devices that have A7 and A8 chips will also be added once an exploit is found.
So should you try the rootlessJB 3.0 on your iOS 12 device? The answer is simple, if you are a developer you can use it for research or development purposes. However if you are an average jailbreak user who is jailbroken on iOS 11 or is waiting for a full iOS 12 jailbreak, then you should stay away from it until an iOS 12 jailbreak that is meant for public is released.
You can try Jake James’ rootlessJB by going to his Github repository.