[18:38:30 FATAL] [mixin]: Mixin failed applying mixins.common.core.json:command.MixinSignCommandSender -> net.minecraft.tileentity.TileEntitySign$2: org.spongepowered.asm.mixin.transformer.InvalidMixinException Shadow field field_174797_a was not located in the target class
org.spongepowered.asm.mixin.transformer.InvalidMixinException: Shadow field field_174797_a was not located in the target class
        at org.spongepowered.asm.mixin.transformer.MixinPreProcessor.attachFields(MixinPreProcessor.java:222) ~[spongevanilla-1.8-2.1-DEV-0.jar:1.8-2.1-DEV-0]
        at org.spongepowered.asm.mixin.transformer.MixinPreProcessor.attach(MixinPreProcessor.java:151) ~[spongevanilla-1.8-2.1-DEV-0.jar:1.8-2.1-DEV-0]
        at org.spongepowered.asm.mixin.transformer.MixinPreProcessor.createContextFor(MixinPreProcessor.java:133) ~[spongevanilla-1.8-2.1-DEV-0.jar:1.8-2.1-DEV-0]
        at org.spongepowered.asm.mixin.transformer.MixinInfo.createContextFor(MixinInfo.java:623) ~[spongevanilla-1.8-2.1-DEV-0.jar:1.8-2.1-DEV-0]
        at org.spongepowered.asm.mixin.transformer.MixinApplicator.apply(MixinApplicator.java:189) ~[spongevanilla-1.8-2.1-DEV-0.jar:1.8-2.1-DEV-0]
        at org.spongepowered.asm.mixin.transformer.MixinTransformer.apply(MixinTransformer.java:644) ~[spongevanilla-1.8-2.1-DEV-0.jar:1.8-2.1-DEV-0]
        at org.spongepowered.asm.mixin.transformer.MixinTransformer.applyMixins(MixinTransformer.java:616) [spongevanilla-1.8-2.1-DEV-0.jar:1.8-2.1-DEV-0]
        at org.spongepowered.asm.mixin.transformer.MixinTransformer.transform(MixinTransformer.java:434) [spongevanilla-1.8-2.1-DEV-0.jar:1.8-2.1-DEV-0]
        at org.spongepowered.asm.mixin.transformer.MixinTransformer$Proxy.transform(MixinTransformer.java:105) [spongevanilla-1.8-2.1-DEV-0.jar:1.8-2.1-DEV-0]
        at net.minecraft.launchwrapper.LaunchClassLoader.runTransformers(LaunchClassLoader.java:279) [launchwrapper-1.12.jar:?]
        at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:176) [launchwrapper-1.12.jar:?]
        at java.lang.ClassLoader.loadClass(Unknown Source) [?:1.8.0_66]
        at java.lang.ClassLoader.loadClass(Unknown Source) [?:1.8.0_66]
        at net.minecraft.tileentity.TileEntitySign.func_174882_b(SourceFile:135) [bdj.class:?]
        at net.minecraft.block.BlockSign.func_180639_a(SourceFile:78) [bai.class:?]
        at net.minecraft.server.management.ItemInWorldManager.func_180236_a(SourceFile:292) [qx.class:?]
        at net.minecraft.network.NetHandlerPlayServer.onActivateBlockOrUseItem(SourceFile:440) [rj.class:?]
        at net.minecraft.network.NetHandlerPlayServer.func_147346_a(SourceFile:452) [rj.class:?]
        at net.minecraft.network.play.client.C08PacketPlayerBlockPlacement.func_180769_a(SourceFile:59) [mx.class:?]
        at net.minecraft.network.play.client.C08PacketPlayerBlockPlacement.func_148833_a(SourceFile:10) [mx.class:?]
        at net.minecraft.network.PacketThreadUtil$1.onProcessPacket(SourceFile:84) [ih.class:?]
        at net.minecraft.network.PacketThreadUtil$1.run(SourceFile:13) [ih.class:?]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_66]
        at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_66]
        at net.minecraft.server.MinecraftServer.func_71190_q(SourceFile:111) [MinecraftServer.class:?]
        at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(SourceFile:305) [po.class:?]
        at net.minecraft.server.MinecraftServer.func_71217_p(SourceFile:531) [MinecraftServer.class:?]
        at net.minecraft.server.MinecraftServer.run(SourceFile:447) [MinecraftServer.class:?]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_66]
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