With Lithium installed I have noticed that creepers don't behave as expected around cats,
The expected behaviour is that they would run away from a cat that is within a 6 block radius however with lithium installed the creeper needs to be within a 2 block radius.

This was tested on Fabric 1.15.2

Happy to provide more information if needed,

Could you cherry-pick 309ff9e back to the 1.15 branch?

@magneticflux- I'm currently working on making some more improvements in this area, but once everything is sound in 1.16 we'll make backports to 1.15. 😄