Before 1.15.2 this problem won't appear.
Before 20w21a, the game will crash when disabling the vanilla data pack by using commands. After the crash, join this world will make Minecraft crash again.
In 20w22a, the game won't crash but still can't disable the vanilla data pack. Here will be some words in chat says "Reload failed, keeping old data" and "Disabled data pack [vanilla]", but the vanilla data pack is still enabling. I think the new snapshot hasn't solved the problem but made the game not crash.
Warns in log (20w22a)
Failed to execute reload java.util.concurrent.CompletionException: java.lang.IllegalStateException: Missing required tags: blocks:minecraft:acacia_logs,blocks:minecraft:anvil,blocks:minecraft:bamboo_plantable_on,blocks:minecraft:banners,blocks:minecraft:beacon_base_blocks,blocks:minecraft:beds,blocks:minecraft:bee_growables,blocks:minecraft:beehives,blocks:minecraft:birch_logs,blocks:minecraft:buttons,blocks:minecraft:campfires,blocks:minecraft:carpets,blocks:minecraft:climbable,blocks:minecraft:coral_blocks,blocks:minecraft:coral_plants,blocks:minecraft:corals,blocks:minecraft:crimson_stems,blocks:minecraft:crops,blocks:minecraft:dark_oak_logs,blocks:minecraft:doors,blocks:minecraft:dragon_immune,blocks:minecraft:enderman_holdable,blocks:minecraft:fence_gates,blocks:minecraft:fences,blocks:minecraft:fire,blocks:minecraft:flower_pots,blocks:minecraft:flowers,blocks:minecraft:gold_ores,blocks:minecraft:guarded_by_piglins,blocks:minecraft:hoglin_repellents,blocks:minecraft:ice,blocks:minecraft:impermeable,blocks:minecraft:jungle_logs,blocks:minecraft:leaves,blocks:minecraft:logs,blocks:minecraft:logs_that_burn,blocks:minecraft:non_flammable_wood,blocks:minecraft:nylium,blocks:minecraft:oak_logs,blocks:minecraft:piglin_repellents,blocks:minecraft:planks,blocks:minecraft:portals,blocks:minecraft:pressure_plates,blocks:minecraft:prevent_mob_spawning_inside,blocks:minecraft:rails,blocks:minecraft:sand,blocks:minecraft:saplings,blocks:minecraft:shulker_boxes,blocks:minecraft:signs,blocks:minecraft:slabs,blocks:minecraft:small_flowers,blocks:minecraft:soul_fire_base_blocks,blocks:minecraft:soul_speed_blocks,blocks:minecraft:spruce_logs,blocks:minecraft:stairs,blocks:minecraft:standing_signs,blocks:minecraft:stone_bricks,blocks:minecraft:stone_pressure_plates,blocks:minecraft:strider_warm_blocks,blocks:minecraft:tall_flowers,blocks:minecraft:trapdoors,blocks:minecraft:underwater_bonemeals,blocks:minecraft:unstable_bottom_center,blocks:minecraft:valid_spawn,blocks:minecraft:wall_corals,blocks:minecraft:wall_post_override,blocks:minecraft:wall_signs,blocks:minecraft:walls,blocks:minecraft:warped_stems,blocks:minecraft:wart_blocks,blocks:minecraft:wither_immune,blocks:minecraft:wither_summon_base_blocks,blocks:minecraft:wooden_buttons,blocks:minecraft:wooden_doors,blocks:minecraft:wooden_fences,blocks:minecraft:wooden_pressure_plates,blocks:minecraft:wooden_slabs,blocks:minecraft:wooden_stairs,blocks:minecraft:wooden_trapdoors,blocks:minecraft:wool,entity_types:minecraft:arrows,entity_types:minecraft:beehive_inhabitors,entity_types:minecraft:impact_projectiles,entity_types:minecraft:raiders,entity_types:minecraft:skeletons,fluids:minecraft:lava,fluids:minecraft:water,items:minecraft:acacia_logs,items:minecraft:anvil,items:minecraft:arrows,items:minecraft:banners,items:minecraft:beacon_payment_items,items:minecraft:beds,items:minecraft:birch_logs,items:minecraft:boats,items:minecraft:buttons,items:minecraft:carpets,items:minecraft:coals,items:minecraft:creeper_drop_music_discs,items:minecraft:crimson_stems,items:minecraft:dark_oak_logs,items:minecraft:doors,items:minecraft:fences,items:minecraft:fishes,items:minecraft:flowers,items:minecraft:furnace_materials,items:minecraft:gold_ores,items:minecraft:jungle_logs,items:minecraft:leaves,items:minecraft:lectern_books,items:minecraft:logs,items:minecraft:logs_that_burn,items:minecraft:music_discs,items:minecraft:non_flammable_wood,items:minecraft:oak_logs,items:minecraft:piglin_loved,items:minecraft:piglin_repellents,items:minecraft:planks,items:minecraft:rails,items:minecraft:sand,items:minecraft:saplings,items:minecraft:signs,items:minecraft:slabs,items:minecraft:small_flowers,items:minecraft:soul_fire_base_blocks,items:minecraft:spruce_logs,items:minecraft:stairs,items:minecraft:stone_bricks,items:minecraft:stone_tool_materials,items:minecraft:tall_flowers,items:minecraft:trapdoors,items:minecraft:walls,items:minecraft:warped_stems,items:minecraft:wooden_buttons,items:minecraft:wooden_doors,items:minecraft:wooden_fences,items:minecraft:wooden_pressure_plates,items:minecraft:wooden_slabs,items:minecraft:wooden_stairs,items:minecraft:wooden_trapdoors,items:minecraft:wool at java.util.concurrent.CompletableFuture.encodeThrowable(CompletableFuture.java:273) at java.util.concurrent.CompletableFuture.completeThrowable(CompletableFuture.java:280) at java.util.concurrent.CompletableFuture.uniAccept(CompletableFuture.java:659) at java.util.concurrent.CompletableFuture$UniAccept.tryFire(CompletableFuture.java:632) at java.util.concurrent.CompletableFuture$Completion.run(CompletableFuture.java:442) at abb.a(SourceFile:71) at abb$$Lambda$2856/130111210.run(Unknown Source) at uu.run(SourceFile:18) at ame.c(SourceFile:144) at ami.c(SourceFile:23) at net.minecraft.server.MinecraftServer.b(SourceFile:749) at net.minecraft.server.MinecraftServer.c(SourceFile:152) at ame.w(SourceFile:118) at net.minecraft.server.MinecraftServer.aY(SourceFile:731) at net.minecraft.server.MinecraftServer.w(SourceFile:725) at ame.c(SourceFile:127) at net.minecraft.server.MinecraftServer.a(SourceFile:1325) at wo.a(SourceFile:22) at vg.a(SourceFile:111) at vg.d(SourceFile:76) at vg$$Lambda$3474/1892843520.run(Unknown Source) at com.mojang.brigadier.CommandDispatcher.execute(CommandDispatcher.java:262) at com.mojang.brigadier.CommandDispatcher.execute(CommandDispatcher.java:176) at cz.a(SourceFile:242) at zr.c(SourceFile:1119) at zr.a(SourceFile:1106) at re.a(SourceFile:36) at re.a(SourceFile:9) at nk.a(SourceFile:21) at nk$$Lambda$4607/1232461173.run(Unknown Source) at uu.run(SourceFile:18) at ame.c(SourceFile:144) at ami.c(SourceFile:23) at net.minecraft.server.MinecraftServer.b(SourceFile:749) at net.minecraft.server.MinecraftServer.c(SourceFile:152) at ame.w(SourceFile:118) at net.minecraft.server.MinecraftServer.aY(SourceFile:731) at net.minecraft.server.MinecraftServer.w(SourceFile:725) at ame.c(SourceFile:127) at net.minecraft.server.MinecraftServer.v(SourceFile:710) at net.minecraft.server.MinecraftServer.run(SourceFile:662) at java.lang.Thread.run(Thread.java:745) Caused by: java.lang.IllegalStateException: Missing required tags: blocks:minecraft:acacia_logs,blocks:minecraft:anvil,blocks:minecraft:bamboo_plantable_on,blocks:minecraft:banners,blocks:minecraft:beacon_base_blocks,blocks:minecraft:beds,blocks:minecraft:bee_growables,blocks:minecraft:beehives,blocks:minecraft:birch_logs,blocks:minecraft:buttons,blocks:minecraft:campfires,blocks:minecraft:carpets,blocks:minecraft:climbable,blocks:minecraft:coral_blocks,blocks:minecraft:coral_plants,blocks:minecraft:corals,blocks:minecraft:crimson_stems,blocks:minecraft:crops,blocks:minecraft:dark_oak_logs,blocks:minecraft:doors,blocks:minecraft:dragon_immune,blocks:minecraft:enderman_holdable,blocks:minecraft:fence_gates,blocks:minecraft:fences,blocks:minecraft:fire,blocks:minecraft:flower_pots,blocks:minecraft:flowers,blocks:minecraft:gold_ores,blocks:minecraft:guarded_by_piglins,blocks:minecraft:hoglin_repellents,blocks:minecraft:ice,blocks:minecraft:impermeable,blocks:minecraft:jungle_logs,blocks:minecraft:leaves,blocks:minecraft:logs,blocks:minecraft:logs_that_burn,blocks:minecraft:non_flammable_wood,blocks:minecraft:nylium,blocks:minecraft:oak_logs,blocks:minecraft:piglin_repellents,blocks:minecraft:planks,blocks:minecraft:portals,blocks:minecraft:pressure_plates,blocks:minecraft:prevent_mob_spawning_inside,blocks:minecraft:rails,blocks:minecraft:sand,blocks:minecraft:saplings,blocks:minecraft:shulker_boxes,blocks:minecraft:signs,blocks:minecraft:slabs,blocks:minecraft:small_flowers,blocks:minecraft:soul_fire_base_blocks,blocks:minecraft:soul_speed_blocks,blocks:minecraft:spruce_logs,blocks:minecraft:stairs,blocks:minecraft:standing_signs,blocks:minecraft:stone_bricks,blocks:minecraft:stone_pressure_plates,blocks:minecraft:strider_warm_blocks,blocks:minecraft:tall_flowers,blocks:minecraft:trapdoors,blocks:minecraft:underwater_bonemeals,blocks:minecraft:unstable_bottom_center,blocks:minecraft:valid_spawn,blocks:minecraft:wall_corals,blocks:minecraft:wall_post_override,blocks:minecraft:wall_signs,blocks:minecraft:walls,blocks:minecraft:warped_stems,blocks:minecraft:wart_blocks,blocks:minecraft:wither_immune,blocks:minecraft:wither_summon_base_blocks,blocks:minecraft:wooden_buttons,blocks:minecraft:wooden_doors,blocks:minecraft:wooden_fences,blocks:minecraft:wooden_pressure_plates,blocks:minecraft:wooden_slabs,blocks:minecraft:wooden_stairs,blocks:minecraft:wooden_trapdoors,blocks:minecraft:wool,entity_types:minecraft:arrows,entity_types:minecraft:beehive_inhabitors,entity_types:minecraft:impact_projectiles,entity_types:minecraft:raiders,entity_types:minecraft:skeletons,fluids:minecraft:lava,fluids:minecraft:water,items:minecraft:acacia_logs,items:minecraft:anvil,items:minecraft:arrows,items:minecraft:banners,items:minecraft:beacon_payment_items,items:minecraft:beds,items:minecraft:birch_logs,items:minecraft:boats,items:minecraft:buttons,items:minecraft:carpets,items:minecraft:coals,items:minecraft:creeper_drop_music_discs,items:minecraft:crimson_stems,items:minecraft:dark_oak_logs,items:minecraft:doors,items:minecraft:fences,items:minecraft:fishes,items:minecraft:flowers,items:minecraft:furnace_materials,items:minecraft:gold_ores,items:minecraft:jungle_logs,items:minecraft:leaves,items:minecraft:lectern_books,items:minecraft:logs,items:minecraft:logs_that_burn,items:minecraft:music_discs,items:minecraft:non_flammable_wood,items:minecraft:oak_logs,items:minecraft:piglin_loved,items:minecraft:piglin_repellents,items:minecraft:planks,items:minecraft:rails,items:minecraft:sand,items:minecraft:saplings,items:minecraft:signs,items:minecraft:slabs,items:minecraft:small_flowers,items:minecraft:soul_fire_base_blocks,items:minecraft:spruce_logs,items:minecraft:stairs,items:minecraft:stone_bricks,items:minecraft:stone_tool_materials,items:minecraft:tall_flowers,items:minecraft:trapdoors,items:minecraft:walls,items:minecraft:warped_stems,items:minecraft:wooden_buttons,items:minecraft:wooden_doors,items:minecraft:wooden_fences,items:minecraft:wooden_pressure_plates,items:minecraft:wooden_slabs,items:minecraft:wooden_stairs,items:minecraft:wooden_trapdoors,items:minecraft:wool at adb.a(SourceFile:81) at adb$$Lambda$3866/1402355598.accept(Unknown Source) at java.util.concurrent.CompletableFuture.uniAccept(CompletableFuture.java:656) ... 39 more
Crash Report (20w21a)
In 20w22a, the game won't crash.
---- Minecraft Crash Report ---- // Would you like a cupcake? Time: 20-5-24 上午11:49 Description: Exception ticking world java.lang.IllegalStateException: Tag minecraft:water used before it was bound at act$a.c(SourceFile:53) at act$a.a(SourceFile:64) at cvx.a(SourceFile:95) at cvy.a(SourceFile:101) at bpi.a(SourceFile:429) at bpi.a(SourceFile:327) at bpi.a(SourceFile:259) at bpi.a(SourceFile:197) at bpi.a(SourceFile:185) at yu.a(SourceFile:384) at yu$$Lambda$4267/677679630.accept(Unknown Source) at java.util.ArrayList.forEach(ArrayList.java:1249) at yu.p(SourceFile:368) at yu.a(SourceFile:337) at yw.a(SourceFile:347) at net.minecraft.server.MinecraftServer.b(SourceFile:893) at net.minecraft.server.MinecraftServer.a(SourceFile:832) at enr.a(SourceFile:89) at net.minecraft.server.MinecraftServer.run(SourceFile:691) at java.lang.Thread.run(Thread.java:745) A detailed walkthrough of the error, its code path and all known details is as follows: --------------------------------------------------------------------------------------- -- Head -- Thread: Server thread Stacktrace: at act$a.c(SourceFile:53) at act$a.a(SourceFile:64) at cvx.a(SourceFile:95) at cvy.a(SourceFile:101) at bpi.a(SourceFile:429) at bpi.a(SourceFile:327) at bpi.a(SourceFile:259) at bpi.a(SourceFile:197) at bpi.a(SourceFile:185) at yu.a(SourceFile:384) at yu$$Lambda$4267/677679630.accept(Unknown Source) at java.util.ArrayList.forEach(ArrayList.java:1249) at yu.p(SourceFile:368) at yu.a(SourceFile:337) at yw.a(SourceFile:347) -- Affected level -- Details: All players: 1 total; [yx['Yoooooory'/307, l='ServerLevel[新的世界]', x=-210.50, y=73.00, z=133.50]] Chunk stats: ServerChunkCache: 2063 Level dimension: minecraft:overworld Level spawn location: World: (-208,71,128), Chunk: (at 0,4,0 in -13,8; contains blocks -208,0,128 to -193,255,143), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511) Level time: 180 game time, 180 day time Level name: 新的世界 Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: true Level weather: Rain time: 117266 (now: false), thunder time: 106227 (now: false) Known server brands: vanilla Level was modded: false Level storage version: 0x04ABD - Anvil Stacktrace: at net.minecraft.server.MinecraftServer.b(SourceFile:893) at net.minecraft.server.MinecraftServer.a(SourceFile:832) at enr.a(SourceFile:89) at net.minecraft.server.MinecraftServer.run(SourceFile:691) at java.lang.Thread.run(Thread.java:745) -- System Details -- Details: Minecraft Version: 20w21a Minecraft Version ID: 20w21a 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: 756574848 bytes (721 MB) / 1140850688 bytes (1088 MB) up to 2147483648 bytes (2048 MB) CPUs: 8 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; [yx['Yoooooory'/307, l='ServerLevel[新的世界]', x=-210.50, y=73.00, z=133.50]] Data Packs: Type: Integrated Server (map_client.txt) Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.