Help please

---- Minecraft Crash Report ----
// I bet Cylons wouldn't have this problem.

Time: 21/7/19 11:00 PM
Description: Exception in server tick loop

java.lang.NoClassDefFoundError: net/minecraft/world/ServerWorld
    at com.sk89q.worldedit.forge.ForgeWorldEdit.setupPlatform(ForgeWorldEdit.java:133) ~[?:?] {}
    at com.sk89q.worldedit.forge.ForgeWorldEdit.serverStarted(ForgeWorldEdit.java:192) ~[?:?] {}
    at net.minecraftforge.eventbus.ASMEventHandler_2_ForgeWorldEdit_serverStarted_FMLServerStartedEvent.invoke(.dynamic) ~[?:?] {}
    at net.minecraftforge.eventbus.ASMEventHandler.invoke(ASMEventHandler.java:80) ~[eventbus-0.10.3-milestone.0.1+1a5fa31-service.jar:?] {}
    at net.minecraftforge.eventbus.EventBus.post(EventBus.java:258) ~[eventbus-0.10.3-milestone.0.1+1a5fa31-service.jar:?] {}
    at net.minecraftforge.fml.server.ServerLifecycleHooks.handleServerStarted(ServerLifecycleHooks.java:81) ~[?:?] {}
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:598) [?:?] {pl:accesstransformer:B}
    at java.lang.Thread.run(Thread.java:745) [?:1.8.0_74] {}
Caused by: java.lang.ClassNotFoundException: net.minecraft.world.ServerWorld
    at java.lang.ClassLoader.findClass(ClassLoader.java:530) ~[?:1.8.0_74] {}
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[?:1.8.0_74] {}
    at cpw.mods.modlauncher.TransformingClassLoader.loadClass(TransformingClassLoader.java:102) ~[modlauncher-3.0.2.jar:?] {}
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[?:1.8.0_74] {}
    ... 8 more

A detailed walkthrough of the error, its code path and all known details is as follows:
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-- System Details --
Details:
    Minecraft Version: 1.14.4
    Minecraft Version ID: 1.14.4
    Operating System: Mac OS X (x86_64) version 10.14.3
    Java Version: 1.8.0_74, Oracle Corporation
    Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
    Memory: 1221195208 bytes (1164 MB) / 2147483648 bytes (2048 MB) up to 2147483648 bytes (2048 MB)
    CPUs: 4
    JVM Flags: 7 total; -Xmx2G -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC -XX:G1NewSizePercent=20 -XX:G1ReservePercent=20 -XX:MaxGCPauseMillis=50 -XX:G1HeapRegionSize=32M
    FML: New FML!
    Loaded coremods (and transformers): Nothing
    Player Count: 0 / 8; []
    Data Packs: mod:worldedit, mod:forge, vanilla
    Type: Integrated Server (map_client.txt)
    Is Modded: Definitely; Client brand changed to 'forge'