In Closed Beta - not yet publicly available
Summary
Script rules allow you to create a Custom JavaScript condition that needs to be met for this rule to be matched.
How to enable
Go to Profile > Project Mapping > Rules
Press Create rule to create a new rule
Once created, press the Edit (Cog Icon) Button.
Once in the Rule configuration press the Edit button to configure a Rule.
Now Press Script Configuration
Once press you will now see the configuration for the Script Rule.