This is a great plugin. Its effects are excellent, and it's perfect for RPG servers. It's a shame it hasn't been updated to version 1.21.1+. Could you please update it to 1.21.1 or higher?
The idea of the plugin is really cool for RPG servers. Although it doesn't present any kind of error in console, and seems to be working on my 1.20.6 server, I think there are some adjustments that need to be made.
The items are not falling flat on the ground, as shown in your image; they fall upright and are "half buried" in the ground. Items are not collected when passing over. We have to right-click on the item to pick them up (is that how it works?). Many times some items collected from the ground simply disappear from the inventory.
I would like the plugin to be updated to the latest versions. It would be an excellent addition to servers!