--- a/net/minecraft/server/DefinedStructureManager.java +++ b/net/minecraft/server/DefinedStructureManager.java @@ -19,7 +19,7 @@ public class DefinedStructureManager { private static final Logger LOGGER = LogManager.getLogger(); - private final Map<MinecraftKey, DefinedStructure> b = Maps.newHashMap(); + private final Map<MinecraftKey, DefinedStructure> b = Maps.newConcurrentMap(); // SPIGOT-5287 private final DataFixer c; private IResourceManager d; private final java.nio.file.Path e;