Originally developed by @Orbitium, HEAVILY patched by @Abdelaziz1586.
Being added to by me (slash1div) as I learn Java.
Similar to DonutSMP spawners. They stack and are fully GUI based. Rates and messages are fully customizable. Even has a playtime restriction on breaking. Also introduces silk-touch requirements for pickup.
You can sell items, open a spawner inventory, and take XP from them. It sells item storage by hooking into Essentials and using its worth.yml list.
When you mine a spawner while sneaking/crouching, it drops a singular one.
When you mine a spawner without crouching, it drops them all.
Without silk touch, you just destroy the spawners.