Since the Electra jailbreak for iOS 11.3.1 is imminent to release, jailbreakers are geting excited about the new jailbreak. A new concept jailbreak called rootlessJB that brings tweaks support to iOS 11.2 - iOS 11.3.1. 

rootlessJB is a proof-of-concept jailbreak for iOS 11.0-11.3.1 with tweak support and SSH access. It is developed by independent developer Jake James.

Rootless jailbreak utilizes Ian Beer’s empty_list exploit and has a success rate of around 40%.

Essentially, it is a watered-down version of the Electra jailbreak toolkit beta that was released back in December. While that’s a good thing, a “rootless” jailbreak can only run Cydia tweaks that don’t require root access

Note – Please do not try this jailbreak on your main Apple device unless you are a developer or a power user. Although the developer believes this tool doesn’t interfere with other tools, it can lead to infinite respring loops and kernel panics. Your best bet right now is to wait for Coolstar to release Electra jailbreak.

This jailbreak was never meant to be a replacement for a full-fledged jailbreak. Here's the list of features. 

• There is no Cydia, and will never have Cydia.
  

• The installation directory is /var/containers/Bundle/tweaksupport, same with Electra Beta.

• There is no rivalry between this jailbrak and Electra jailbreak, the developer claims.

• Remove button is available.

• PreferenceLoader and launchctl is missing.

• Tweak support is limited only to the Messages app, SpringBoard, Home, and Clock.

• App-specific tweaks are non-functional.

If you want to know how to install it, please refer Jake James' Twitter.