Game crash corrupts level.dat

[Purpule-Mongoose]

Context

A crash to do with sable causes the server to stop and crash, (the second bit of text below), but after the server tries to start back up, it stops starting partway through, with this error:

[main/WARN] [minecraft/Main]: Failed to load datapacks, can't proceed with server load. You can either fix your datapacks or reset to vanilla with --safeMode
java.util.concurrent.ExecutionException: java.lang.IllegalStateException: No key dimensions in MapLike[{}]; No key seed in MapLike[{}]
at java.base/java.util.concurrent.CompletableFuture.reportGet(CompletableFuture.java:396) ~[?:?] {re:mixin}
at java.base/java.util.concurrent.CompletableFuture.get(CompletableFuture.java:2073) ~[?:?] {re:mixin}
at TRANSFORMER/minecraft@1.21.1/net.minecraft.server.Main.main(Main.java:258) ~[server-1.21.1-20240808.144430-srg.jar%23222!/:?] {re:classloading}
at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103) ~[?:?] {}
at java.base/java.lang.reflect.Method.invoke(Method.java:580) ~[?:?] {}
at MC-BOOTSTRAP/fml_loader@4.0.44/net.neoforged.fml.loading.targets.CommonLaunchHandler.runTarget(CommonLaunchHandler.java:136) ~[loader-4.0.44.jar%2359!/:4.0] {}
at MC-BOOTSTRAP/fml_loader@4.0.44/net.neoforged.fml.loading.targets.CommonLaunchHandler.serverService(CommonLaunchHandler.java:128) ~[loader-4.0.44.jar%2359!/:4.0] {}
at MC-BOOTSTRAP/fml_loader@4.0.44/net.neoforged.fml.loading.targets.CommonServerLaunchHandler.runService(CommonServerLaunchHandler.java:32) ~[loader-4.0.44.jar%2359!/:4.0] {}
at MC-BOOTSTRAP/fml_loader@4.0.44/net.neoforged.fml.loading.targets.CommonLaunchHandler.lambda$launchService$4(CommonLaunchHandler.java:118) ~[loader-4.0.44.jar%2359!/:4.0] {}
at MC-BOOTSTRAP/cpw.mods.modlauncher@11.0.5/cpw.mods.modlauncher.LaunchServiceHandlerDecorator.launch(LaunchServiceHandlerDecorator.java:30) [modlauncher-11.0.5.jar%2364!/:?] {}
at MC-BOOTSTRAP/cpw.mods.modlauncher@11.0.5/cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:53) [modlauncher-11.0.5.jar%2364!/:?] {}
at MC-BOOTSTRAP/cpw.mods.modlauncher@11.0.5/cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:71) [modlauncher-11.0.5.jar%2364!/:?] {}
at MC-BOOTSTRAP/cpw.mods.modlauncher@11.0.5/cpw.mods.modlauncher.Launcher.run(Launcher.java:103) [modlauncher-11.0.5.jar%2364!/:?] {}
at MC-BOOTSTRAP/cpw.mods.modlauncher@11.0.5/cpw.mods.modlauncher.Launcher.main(Launcher.java:74) [modlauncher-11.0.5.jar%2364!/:?] {}
at MC-BOOTSTRAP/cpw.mods.modlauncher@11.0.5/cpw.mods.modlauncher.BootstrapLaunchConsumer.accept(BootstrapLaunchConsumer.java:26) [modlauncher-11.0.5.jar%2364!/:?] {}
at MC-BOOTSTRAP/cpw.mods.modlauncher@11.0.5/cpw.mods.modlauncher.BootstrapLaunchConsumer.accept(BootstrapLaunchConsumer.java:23) [modlauncher-11.0.5.jar%2364!/:?] {}
at cpw.mods.bootstraplauncher@2.0.2/cpw.mods.bootstraplauncher.BootstrapLauncher.run(BootstrapLauncher.java:210) [bootstraplauncher-2.0.2.jar:?] {}
at cpw.mods.bootstraplauncher@2.0.2/cpw.mods.bootstraplauncher.BootstrapLauncher.main(BootstrapLauncher.java:69) [bootstraplauncher-2.0.2.jar:?] {}
Caused by: java.lang.IllegalStateException: No key dimensions in MapLike[{}]; No key seed in MapLike[{}]
at MC-BOOTSTRAP/datafixerupper@8.0.16/com.mojang.serialization.DataResult$Error.getOrThrow(DataResult.java:287) ~[datafixerupper-8.0.16.jar%23100!/:?] {re:mixin}
at MC-BOOTSTRAP/datafixerupper@8.0.16/com.mojang.serialization.DataResult.getOrThrow(DataResult.java:81) ~[datafixerupper-8.0.16.jar%23100!/:?] {re:mixin}
at TRANSFORMER/minecraft@1.21.1/net.minecraft.world.level.storage.LevelStorageSource.getLevelDataAndDimensions(LevelStorageSource.java:140) ~[server-1.21.1-20240808.144430-srg.jar%23222!/:?] {re:classloading}
at TRANSFORMER/minecraft@1.21.1/net.minecraft.server.Main.lambda$main$2(Main.java:210) ~[server-1.21.1-20240808.144430-srg.jar%23222!/:?] {re:classloading}
at TRANSFORMER/minecraft@1.21.1/net.minecraft.server.WorldLoader.load(WorldLoader.java:43) ~[server-1.21.1-20240808.144430-srg.jar%23222!/:?] {re:mixin,re:classloading,pl:mixin:APP:modernfix-modernfix.mixins.json:feature.measure_time.WorldLoaderMixin from mod modernfix,pl:mixin:APP:modernfix-modernfix.mixins.json:core.WorldLoaderMixin from mod modernfix,pl:mixin:APP:moonlight-common.mixins.json:WorldLoaderMixin from mod moonlight,pl:mixin:A}
at TRANSFORMER/minecraft@1.21.1/net.minecraft.server.Main.lambda$main$3(Main.java:205) ~[server-1.21.1-20240808.144430-srg.jar%23222!/:?] {re:classloading}
at TRANSFORMER/minecraft@1.21.1/net.minecraft.Util.blockUntilDone(Util.java:866) ~[server-1.21.1-20240808.144430-srg.jar%23222!/:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,pl:mixin:APP:modernfix-modernfix.mixins.json:perf.thread_priorities.UtilMixin from mod modernfix,pl:mixin:A}
at TRANSFORMER/minecraft@1.21.1/net.minecraft.Util.blockUntilDone(Util.java:861) ~[server-1.21.1-20240808.144430-srg.jar%23222!/:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,pl:mixin:APP:modernfix-modernfix.mixins.json:perf.thread_priorities.UtilMixin from mod modernfix,pl:mixin:A}
at TRANSFORMER/minecraft@1.21.1/net.minecraft.server.Main.main(Main.java:204) ~[server-1.21.1-20240808.144430-srg.jar%23222!/:?] {re:classloading}
... 15 more

Probably relevant information: Upon opening the level.dat after the crash, there is no WorldGenSettings folder in there.

Crash Report

https://mclo.gs/HOlp4MW