[17:32:21] [Server thread/WARN]: Chunk generation via Bukkit raised an error
java.lang.UnsupportedOperationException: Not supported in this Minecraft version! Unless you can fix it, this is not a bug :)
        at org.bukkit.craftbukkit.v1_14_R1.CraftWorld.regenerateChunk(CraftWorld.java:408) ~[spigot-1.14.4.jar:git-Spigot-56f8471-6567017]
        at com.sk89q.worldedit.bukkit.BukkitWorld.regenerate(BukkitWorld.java:191) ~[?:?]
        at com.sk89q.worldedit.command.RegionCommands.regenerateChunk(RegionCommands.java:402) ~[?:?]
        at com.sk89q.worldedit.command.RegionCommandsRegistration._regen(RegionCommandsRegistration.java:567) ~[?:?]
        at org.enginehub.piston.CommandManager.execute(CommandManager.java:158) ~[?:?]
        at com.sk89q.worldedit.extension.platform.PlatformCommandManager.handleCommand(PlatformCommandManager.java:471) ~[?:?]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_231]
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_231]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_231]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_231]
        at com.sk89q.worldedit.util.eventbus.MethodEventHandler.dispatch(MethodEventHandler.java:58) ~[?:?]
        at com.sk89q.worldedit.util.eventbus.EventHandler.handleEvent(EventHandler.java:73) ~[?:?]
        at com.sk89q.worldedit.util.eventbus.EventBus.nonwrapped_dispatch(EventBus.java:193) ~[?:?]
        at com.sk89q.worldedit.util.eventbus.EventBus.dispatch(EventBus.java) ~[?:?]
        at com.sk89q.worldedit.util.eventbus.EventBus.nonwrapped_post(EventBus.java:181) ~[?:?]
        at com.sk89q.worldedit.util.eventbus.EventBus.post(EventBus.java) ~[?:?]
        at com.sk89q.worldedit.bukkit.WorldEditPlugin.onCommand(WorldEditPlugin.java:341) ~[?:?]
        at com.sk89q.bukkit.util.DynamicPluginCommand.execute(DynamicPluginCommand.java:55) ~[?:?]
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:149) ~[spigot-1.14.4.jar:git-Spigot-56f8471-6567017]
        at org.bukkit.craftbukkit.v1_14_R1.CraftServer.dispatchCommand(CraftServer.java:710) ~[spigot-1.14.4.jar:git-Spigot-56f8471-6567017]
        at net.minecraft.server.v1_14_R1.PlayerConnection.handleCommand(PlayerConnection.java:1641) ~[spigot-1.14.4.jar:git-Spigot-56f8471-6567017]
        at net.minecraft.server.v1_14_R1.PlayerConnection.a(PlayerConnection.java:1481) ~[spigot-1.14.4.jar:git-Spigot-56f8471-6567017]
        at net.minecraft.server.v1_14_R1.PacketPlayInChat.a(PacketPlayInChat.java:47) ~[spigot-1.14.4.jar:git-Spigot-56f8471-6567017]
        at net.minecraft.server.v1_14_R1.PacketPlayInChat.a(PacketPlayInChat.java:1) ~[spigot-1.14.4.jar:git-Spigot-56f8471-6567017]
        at net.minecraft.server.v1_14_R1.PlayerConnectionUtils.lambda$0(PlayerConnectionUtils.java:19) ~[spigot-1.14.4.jar:git-Spigot-56f8471-6567017]
        at net.minecraft.server.v1_14_R1.TickTask.run(SourceFile:18) [spigot-1.14.4.jar:git-Spigot-56f8471-6567017]
        at net.minecraft.server.v1_14_R1.IAsyncTaskHandler.executeTask(SourceFile:144) [spigot-1.14.4.jar:git-Spigot-56f8471-6567017]
        at net.minecraft.server.v1_14_R1.IAsyncTaskHandlerReentrant.executeTask(SourceFile:23) [spigot-1.14.4.jar:git-Spigot-56f8471-6567017]
        at net.minecraft.server.v1_14_R1.IAsyncTaskHandler.executeNext(SourceFile:118) [spigot-1.14.4.jar:git-Spigot-56f8471-6567017]
        at net.minecraft.server.v1_14_R1.MinecraftServer.aX(MinecraftServer.java:909) [spigot-1.14.4.jar:git-Spigot-56f8471-6567017]
        at net.minecraft.server.v1_14_R1.MinecraftServer.executeNext(MinecraftServer.java:902) [spigot-1.14.4.jar:git-Spigot-56f8471-6567017]
        at net.minecraft.server.v1_14_R1.IAsyncTaskHandler.awaitTasks(SourceFile:127) [spigot-1.14.4.jar:git-Spigot-56f8471-6567017]
        at net.minecraft.server.v1_14_R1.MinecraftServer.sleepForTick(MinecraftServer.java:886) [spigot-1.14.4.jar:git-Spigot-56f8471-6567017]
        at net.minecraft.server.v1_14_R1.MinecraftServer.run(MinecraftServer.java:819) [spigot-1.14.4.jar:git-Spigot-56f8471-6567017]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_231]