Have you ever noticed that the Copper ores drops more Raw Copper? It always makes inventories filled with bunch of coppers, which, in most cases, is useless.
Drop Like Copper changes the looting behavior of other ores, making them drop as much as coppers do.
By the way, Drop Like Copper can also be used as a library for looting stuff, lmk if you want more features.
Calling DropLikeCopperAPI.setLibraryMode() will disable the default behavior of Drop Like Copper.
It introduced few events for you to manipulate the looting table, like LootingEvent.LootingPool.
You can find an example in cn.elytra.mod.drop_like_copper.internal.DropLikeCopperCore, which is the default behavior.
And some handy delegate classes in cn.elytra.mod.drop_like_copper.api.delegate when manipulating them.