How can i restringe drop an item?

MCreator has a "hidden" built-in event system that can stop an item from dropping. All you need to do is create a procedure, open the dropdown menu at the top block ("no additional trigger") and select "Gem dropped". Then make an "if" block that detects if "provided item" = the item you want to stop from dropping. In that block, I think you should be able to cancel the event by getting a custom code snippet from the Advanced section and writing exactly this:

event.setCanceled(true);

Include the semicolon.

Tell me if it works because this would actually be pretty useful information for me to know as well.