Spawners don't take nbt in consideration when the player is in survival.

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Spawners don't take nbt in consideration when the player is in survival.
If we've got a spawner who spawns zombies, it's wanted, so why can't we place him in survival?
The spawner will always appear with pigs.

give @s spawner{BlockEntityTag:{SpawnData:{id:"minecraft:creeper"}, SpawnPotentials: [{Entity: {id: "minecraft:creeper"}, Weight: 1}]}} 1