Fatal game crash - Polar Bear vehicle NPE

---- Minecraft Crash Report ----
// Sorry :(

Time: 01.11.18 22:31
Description: Ticking entity

java.lang.NullPointerException: Ticking entity
	at ajr.g(SourceFile:81)
	at alj$c.c(SourceFile:231)
	at aia.a(SourceFile:102)
	at agf.cQ(SourceFile:603)
	at age.k(SourceFile:2026)
	at agf.k(SourceFile:472)
	at afs.k(SourceFile:134)
	at akw.k(SourceFile:46)
	at age.S_(SourceFile:1877)
	at agf.S_(SourceFile:285)
	at alj.S_(SourceFile:155)
	at azt.a(SourceFile:1164)
	at ua.a(SourceFile:380)
	at azt.g(SourceFile:1144)
	at azt.n_(SourceFile:1026)
	at ua.n_(SourceFile:296)
	at net.minecraft.server.MinecraftServer.b(SourceFile:756)
	at net.minecraft.server.MinecraftServer.a(SourceFile:685)
	at dlv.a(SourceFile:128)
	at net.minecraft.server.MinecraftServer.run(SourceFile:573)
	at java.lang.Thread.run(Thread.java:745)


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Thread: Server thread
Stacktrace:
	at ajr.g(SourceFile:81)
	at alj$c.c(SourceFile:231)
	at aia.a(SourceFile:102)
	at agf.cQ(SourceFile:603)
	at age.k(SourceFile:2026)
	at agf.k(SourceFile:472)
	at afs.k(SourceFile:134)
	at akw.k(SourceFile:46)
	at age.S_(SourceFile:1877)
	at agf.S_(SourceFile:285)
	at alj.S_(SourceFile:155)
	at azt.a(SourceFile:1164)
	at ua.a(SourceFile:380)
	at azt.g(SourceFile:1144)

-- Entity being ticked --
Details:
	Entity Type: minecraft:polar_bear (alj)
	Entity ID: 312
	Entity Name: Polar Bear
	Entity's Exact location: 143.53, 80.79, 376.25
	Entity's Block location: World: (143,80,376), Chunk: (at 15,5,8 in 8,23; contains blocks 128,0,368 to 143,255,383), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Entity's Momentum: 0.19, -0.20, 0.32
	Entity's Passengers: []
	Entity's Vehicle: ~~ERROR~~ NullPointerException: null
Stacktrace:
	at azt.n_(SourceFile:1026)
	at ua.n_(SourceFile:296)

-- Affected level --
Details:
	Level name: New World
	All players: 1 total; [uc['Amadeone'/210, l='New World', x=141.50, y=82.87, z=375.37]]
	Chunk stats: ServerChunkCache: 7225
	Level seed: 2347794480153192892
	Level generator: ID 00 - default, ver 1. Features enabled: true
	Level generator options: {}
	Level spawn location: World: (224,79,65), Chunk: (at 0,4,1 in 14,4; contains blocks 224,0,64 to 239,255,79), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Level time: 8583 game time, 8583 day time
	Level dimension: 0
	Level storage version: 0x04ABD - Anvil
	Level weather: Rain time: 93942 (now: false), thunder time: 144895 (now: false)
	Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: true
Stacktrace:
	at net.minecraft.server.MinecraftServer.b(SourceFile:756)
	at net.minecraft.server.MinecraftServer.a(SourceFile:685)
	at dlv.a(SourceFile:128)
	at net.minecraft.server.MinecraftServer.run(SourceFile:573)
	at java.lang.Thread.run(Thread.java:745)

-- System Details --
Details:
	Minecraft Version: 18w44a
	Operating System: Windows 10 (amd64) version 10.0
	Java Version: 1.8.0_51, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 762063704 bytes (726 MB) / 2147483648 bytes (2048 MB) up to 2147483648 bytes (2048 MB)
	JVM Flags: 9 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xss1M -Xmx2G -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC -XX:G1NewSizePercent=20 -XX:G1ReservePercent=20 -XX:MaxGCPauseMillis=50 -XX:G1HeapRegionSize=32M
	Player Count: 1 / 8; [uc['Amadeone'/210, l='New World', x=141.50, y=82.87, z=375.37]]
	Data Packs: vanilla
	Type: Integrated Server (map_client.txt)
	Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.