After you break a monster spawner, the particles that the spawner emits are still created despite the spawner not existing anymore. The small mob inside is also present.
Environment
Minecraft Version: 1.3.1
Operating System: Windows 10 (amd64) version 10.0
Java Version: 1.8.0_51, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle
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However, this issue is a Duplicate of MC-137463.
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