What's new?
The zombie limit per chunk now works again on latest versions of PaperMC (it already worked on Spigot). PaperMC apparently decided to introduce changes to their API, which broke this functionality previously.

How to install
Download the new jar file from this page. Put it into your plugins folder and remove the old jar file. Restart your server and everything has been updated, the new setting will be added to your configuration file automatically!