[18:50:25] [Server thread/ERROR]: Error occurred while enabling Skript v2.3.6 (Is it up to date?)
java.lang.ExceptionInInitializerError: null
    at ch.njol.skript.aliases.Aliases.<clinit>(Aliases.java:143) ~[?:?]
    at ch.njol.skript.Skript.onEnable(Skript.java:397) ~[?:?]
    at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:264) ~[spigot.jar:git-Spigot-dcd1643-e60fc34]
    at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:337) [spigot.jar:git-Spigot-dcd1643-e60fc34]
    at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:403) [spigot.jar:git-Spigot-dcd1643-e60fc34]
    at org.bukkit.craftbukkit.v1_12_R1.CraftServer.enablePlugin(CraftServer.java:381) [spigot.jar:git-Spigot-dcd1643-e60fc34]
    at org.bukkit.craftbukkit.v1_12_R1.CraftServer.enablePlugins(CraftServer.java:330) [spigot.jar:git-Spigot-dcd1643-e60fc34]
    at net.minecraft.server.v1_12_R1.MinecraftServer.t(MinecraftServer.java:422) [spigot.jar:git-Spigot-dcd1643-e60fc34]
    at net.minecraft.server.v1_12_R1.MinecraftServer.l(MinecraftServer.java:383) [spigot.jar:git-Spigot-dcd1643-e60fc34]
    at net.minecraft.server.v1_12_R1.MinecraftServer.a(MinecraftServer.java:338) [spigot.jar:git-Spigot-dcd1643-e60fc34]
    at net.minecraft.server.v1_12_R1.DedicatedServer.init(DedicatedServer.java:272) [spigot.jar:git-Spigot-dcd1643-e60fc34]
    at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:545) [spigot.jar:git-Spigot-dcd1643-e60fc34]
    at java.lang.Thread.run(Thread.java:748) [?:1.8.0_232]
Caused by: java.lang.IllegalArgumentException: No enum constant org.bukkit.Material.ACACIA_BOAT
    at java.lang.Enum.valueOf(Enum.java:238) ~[?:1.8.0_232]
    at org.bukkit.Material.valueOf(Material.java:1) ~[spigot.jar:git-Spigot-dcd1643-e60fc34]
    at ch.njol.skript.aliases.MaterialRegistry.load(MaterialRegistry.java:61) ~[?:?]
    at ch.njol.skript.aliases.ItemData.<clinit>(ItemData.java:104) ~[?:?]
    ... 13 more