Ability to create empty mob spawners

It is possible to create an empty mob spawner with any regular mob spawner. This will make the spawner useless, since it'll be empty. It is also not possible to use this to create another type of spawner with spawn eggs. - Hold the spawner you wish to destroy in your off-hand - Hold a Lily Pad in your main hand - Attempt to place down the Lily Pad on any block it cannot be placed on - The spawner in your off-hand will be placed as an empty spawner