after making cuboid (get of my lawn), and add myself as a owner, my friend teleport to me and he click on the stuff, after click on the chest, server crashed.

Heres log:

---- Minecraft Crash Report ----
// Ouch. That hurt :(

Time: 2/20/21 9:29 PM
Description: Exception in server tick loop

java.lang.NoClassDefFoundError: com/therandomlabs/vanilladeathchest/util/DeathChestBlockEntity
at draylar.goml.api.compat.DeathChestsCompat.lambda$register$0(DeathChestsCompat.java:19)
at draylar.goml.EventHandlers.testPermission(EventHandlers.java:96)
at draylar.goml.EventHandlers.lambda$registerInteractBlockCallback$2(EventHandlers.java:58)
at net.fabricmc.fabric.api.event.player.UseBlockCallback.lambda$static$0(UseBlockCallback.java:41)
at net.minecraft.class_3225.handler$zii000$interactBlock(class_3225.java:2570)
at net.minecraft.class_3225.method_14262(class_3225.java)
at net.minecraft.class_3244.method_12046(class_3244.java:1040)
at net.minecraft.class_2885.method_12547(class_2885.java:36)
at net.minecraft.class_2885.method_11054(class_2885.java:10)
at net.minecraft.class_2600.method_11072(class_2600.java:21)
at net.minecraft.class_3738.run(class_3738.java:18)
at net.minecraft.class_1255.method_18859(class_1255.java:144)
at net.minecraft.class_4093.method_18859(class_4093.java:23)
at net.minecraft.server.MinecraftServer.method_24306(MinecraftServer.java:761)
at net.minecraft.server.MinecraftServer.method_18859(MinecraftServer.java:155)
at net.minecraft.class_1255.method_16075(class_1255.java:118)
at net.minecraft.server.MinecraftServer.method_20415(MinecraftServer.java:743)
at net.minecraft.server.MinecraftServer.method_16075(MinecraftServer.java:737)
at net.minecraft.class_1255.method_18857(class_1255.java:127)
at net.minecraft.server.MinecraftServer.method_16208(MinecraftServer.java:722)
at net.minecraft.server.MinecraftServer.method_29741(MinecraftServer.java:674)
at net.minecraft.server.MinecraftServer.method_29739(MinecraftServer.java:257)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.ClassNotFoundException: com.therandomlabs.vanilladeathchest.util.DeathChestBlockEntity
at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at net.fabricmc.loader.launch.server.InjectingURLClassLoader.loadClass(InjectingURLClassLoader.java:56)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at net.fabricmc.loader.launch.knot.KnotClassLoader.loadClass(KnotClassLoader.java:168)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 23 more

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

-- System Details --
Details:
Minecraft Version: 1.16.5
Minecraft Version ID: 1.16.5
Operating System: Linux (amd64) version 5.4.0-52-generic
Java Version: 1.8.0_201, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 308697800 bytes (294 MB) / 2790260736 bytes (2661 MB) up to 7635730432 bytes (7282 MB)
CPUs: 2
JVM Flags: 7 total; -Xms256M -Xmx8192M -XX:MinHeapFreeRatio=2 -XX:MaxHeapFreeRatio=7 -XX:ParallelGCThreads=2 -XX:CICompilerCount=2 -XX:ActiveProcessorCount=2
Fabric Mods:
addendum: Addendum 1.16.5-1.0.2
adorn: Adorn 1.13.0+1.16.5
advanced_runtime_resource_pack: Runtime Resource Pack 0.2.9
advdebug: Advancements Debug 2.2.0
angerable-patch: Angerable Patch 1.1.0-1.16.4
appleskin: AppleSkin 1.0.11
appliedenergistics2: Applied Energistics 2 8.1.0-alpha.13
architectury: Architectury 1.7.117
artifacts: Artifacts 2.3.0+fabric
artifice: Artifice 0.14.6+1.16.5
artofalchemy: Art of Alchemy: Memoriam 1.0.0-rc4+1.16.4
attributefix: Attribute Fix {FABRIC} 1.0.1
autoconfig1u: Auto Config v1 Updated 3.3.1
bambootweaks: Bamboo Tweaks unspecified
battletowers: Battle Towers 3.3.2-1.16.4
bedspreads: Bedspreads 1.3.1-1.16.4
bettercaves: YUNG's Better Caves 1.16.2-1.0.3
betterend: Better End 0.9.1-pre
bettermineshafts: YUNG's Better Mineshafts 1.16.4-1.0
betterthanmending: BetterThanMending 1.2.0
biome_locator: Biome Locator 1.1.2
biomemakeover: Biome Makeover 1.16.4-1.2.11
blast: BLAST 1.5
blockshifter: Blockshifter 1.3.2+fabric-1.16.4
blockus: Blockus 2.0.2+1.16.4
blue_endless_jankson: jankson 1.2.0
byg: BYG 1.1.5
campanion: Campanion 1.3.4
cardinal-components: Cardinal Components API 2.7.12
cardinal-components-base: Cardinal Components API (base) 2.7.12
cardinal-components-block: Cardinal Components API (blocks) 2.7.12
cardinal-components-chunk: Cardinal Components API (chunks) 2.7.12
cardinal-components-entity: Cardinal Components API (entities) 2.7.12
cardinal-components-item: Cardinal Components API (items) 2.7.12
cardinal-components-level: Cardinal Components API (world saves) 2.7.12
cardinal-components-scoreboard: Cardinal Components API (scoreboard) 2.7.12
cardinal-components-util: Cardinal Components API (utilities) 2.7.12
cardinal-components-world: Cardinal Components API (worlds) 2.7.12
carrier: Carrier 1.7.4
cavebiomes: Cave Biomes 0.6.2
chainmail: Chainmail 0.5.0
charm: Charm 2.2.2
charmonium: Charmonium 2.2.2
chunkpregen: Fabric Chunk Pregenerator 0.3.3
cinderscapes: Cinderscapes 1.3.3
cleancut: CleanCut mc1.16-2.1-fabric
cloth-api: Cloth API 1.4.9
cloth-armor-api-v1: Cloth Armor API v1 1.4.9
cloth-basic-math: Cloth Basic Math 0.5.1
cloth-client-events-v0: Cloth Client Events v0 1.5.47
cloth-common-events-v1: Cloth Common Events v1 1.4.9
cloth-config2: Cloth Config v4 4.10.13
cloth-datagen-api-v1: Cloth Datagen v1 1.4.9
cloth-durability-bar-api-v1: Cloth Durability Bar API v1 1.5.47
cloth-dynamic-registry-api-v1: Cloth Dynamic Registry API v1 1.4.9
cloth-utils-v1: Cloth Utils v1 1.4.9
com_electronwill_night-config_core: core 3.6.2
com_electronwill_night-config_toml: toml 3.6.2
com_github_nathanpb_safer: Safer 1.1.0
com_github_therandomlabs_trlutils-config: TRLUtils-Config master-SNAPSHOT
com_github_therandomlabs_trlutils-fabric: TRLUtils-Fabric 1.16-SNAPSHOT
com_moandjiezana_toml_toml4j: toml4j 0.7.2
compressedblocks: Compressed Blocks 1.0
computercraft: CC:T for Fabric 1.91.2
controlling: Controlling For Fabric 1.1.2
couplings: Couplings 1.3.3
crookedcrooks: Crooked Crooks 1.3.3+1.16.4
croptopia: Croptopia 1.2.0
croptosis: Croptosis 1.0.1
crowdin-translate: CrowdinTranslate 1.2
crusade: Crusade 1.2.0
dankstorage: Dank Storage 1.9a-1.16.3
darkpaintings: Dark Paintings 3.0.1
dawn: Dawn API 1.6.5
decimal_coins: Decimal Coins 1.16.2-1.2.0
diggusmaximus: Diggus Maximus 1.4.2-1.16.3
dml-refabricated: Deep Mob Learning: Refabricated 0.3.1-beta5
dwarfcoal: Dwarf Coal 1.16.2-1.0.0
ecotones: Ecotones 0.7.1
enchantmentdescriptions: Enchantment Descriptions 2.0.1
expandedstorage: ExpandedStorage 5.6.32
ezpas: Ezpas 1.2.3-1.16.2
fabric: Fabric API 0.30.3+1.16
fabric-api-base: Fabric API Base 0.2.1+9354966b7d
fabric-api-lookup-api-v1: Fabric Api Lookup API (v1) 1.0.0+8f91dfb63a
fabric-biome-api-v1: Fabric Biome API (v1) 3.1.1+ca58154a7d
fabric-command-api-v1: Fabric Command API (v1) 1.0.10+ca58154a7d
fabric-commands-v0: Fabric Commands (v0) 0.2.2+ca58154a7d
fabric-containers-v0: Fabric Containers (v0) 0.1.11+9354966b7d
fabric-content-registries-v0: Fabric Content Registries (v0) 0.2.1+ca58154a7d
fabric-crash-report-info-v1: Fabric Crash Report Info (v1) 0.1.3+ca58154a7d
fabric-dimensions-v1: fabric-dimensions-v1 2.0.6+9354966b7d
fabric-entity-events-v1: Fabric Entity Events (v1) 1.0.3+ca58154a7d
fabric-events-interaction-v0: Fabric Events Interaction (v0) 0.4.2+ca58154a7d
fabric-events-lifecycle-v0: Fabric Events Lifecycle (v0) 0.2.1+ca58154a7d
fabric-furnaces: Fabric Furnaces 1.3.3-1.16.4
fabric-game-rule-api-v1: Fabric Game Rule API (v1) 1.0.6+ca58154a7d
fabric-item-api-v1: Fabric Item API (v1) 1.2.1+ca58154a7d
fabric-item-groups-v0: Fabric Item Groups (v0) 0.2.3+ca58154a7d
fabric-language-kotlin: Fabric Language Kotlin 1.4.21+build.1
fabric-language-scala: Fabric Language Scala 1.0.0
fabric-lifecycle-events-v1: Fabric Lifecycle Events (v1) 1.2.1+ca58154a7d
fabric-loot-tables-v1: Fabric Loot Tables (v1) 1.0.2+ca58154a7d
fabric-mining-levels-v0: Fabric Mining Levels (v0) 0.1.3+ca58154a7d
fabric-networking-api-v1: Fabric Networking API (v1) 1.0.1+ca58154a7d
fabric-networking-blockentity-v0: Fabric Networking Block Entity (v0) 0.2.8+ca58154a7d
fabric-networking-v0: Fabric Networking (v0) 0.3.2+ca58154a7d
fabric-object-builder-api-v1: Fabric Object Builder API (v1) 1.9.4+9354966b7d
fabric-object-builders-v0: Fabric Object Builders (v0) 0.7.2+ca58154a7d
fabric-particles-v1: Fabric Particles (v1) 0.2.4+ca58154a7d
fabric-registry-sync-v0: Fabric Registry Sync (v0) 0.7.4+ca58154a7d
fabric-rendering-data-attachment-v1: Fabric Rendering Data Attachment (v1) 0.1.5+ca58154a7d
fabric-resource-loader-v0: Fabric Resource Loader (v0) 0.4.2+ca58154a7d
fabric-screen-handler-api-v1: Fabric Screen Handler API (v1) 1.1.5+9354966b7d
fabric-structure-api-v1: Fabric Structure API (v1) 1.1.4+ca58154a7d
fabric-tag-extensions-v0: Fabric Tag Extensions (v0) 1.1.1+ca58154a7d
fabric-tool-attribute-api-v1: Fabric Tool Attribute API (v1) 1.2.6+ca58154a7d
fabricloader: Fabric Loader 0.11.1
fallflyinglib: FallFlyingLib 1.1.0
fasttransferlib: Fast Transfer Lib 0.2.2
fatxporbs: Fat Experience Orbs 0.0.9
fermion: Fermion 2.9.218
fermion-gui: Fermion GUI 2.5.218
fermion-modkeys: Fermion Modifier Keys 1.10.218
fermion-orientation: Fermion Orientation 1.2.218
fermion-simulator: Fermion Simulator 1.8.218
fermion-varia: Fermion Varia 2.6.218
fiber: fiber 0.23.0-2
flamingo_ooo: Flamingo, oh, oh, oh... 1.0.4-MC1.16.3-fabric
flonters: Flonters 1.1.1+1.16.2
flora-doubling: Flora Doubling 1.3.0+1.16.4-fabric
flytre_lib: FlytreLib 0.2.5
gateofbabylon: Gate Of Babylon 1.2.1-1.16.2
givemehats: Give Me Hats! 1.4
glassdoor: Glass Doors 1.5.0-1.16
glassential: Glassential 1.16.4-1.1.5
go-fish: Go Fish 1.2.1-beta-1.16.4
golemsgalore: Golems Galore 0.2.0+mc.1.16.2
goml: Get Off My Lawn 1.3.2-beta
grindenchantments: Grind Enchantments 1.1.3+1.16.3
hard-hat-steve: Hard Hat Steve 1.2.0
hardcorequesting: Hardcore Questing Mode 1.16.2+5.5.6
harvest: Harvest 1.2.12
harvest_scythes: Harvest Scythes 1.0.9
hctm-base: HCTM Base 3.5.1
horseinfo: Horse Info 0.2.2-1.16.1
ignis-fatuus: Ignis Fatuus 1.1.3
improved-stations: Improved Stations 2.0.3
indrev: Industrial Revolution 1.8.4-BETA
inmis: Inmis 2.1.1-1.16.4
inventorysorter: Inventory Sorter 1.7.7-1.16
invtrashslot: InvTrashSlot 1.0.2
iron-jetpacks: Iron Jetpacks 0.2.5
jankson: Jankson 3.0.1+j1.2.0
java: Java HotSpot(TM) 64-Bit Server VM 8
javax_vecmath_vecmath: vecmath 1.5.2
jumploader: Jumploader 2.1.2
kibe: Kibe 1.6.3-BETA
ktdatataglib: KtDataTagLib 1.4.0
kubejs: KubeJS 1605.3.6-build.168
kyrptconfig: Kytpt Config 1.1.6-1.16
lapisreserve: Lapis Reserve 1.0.6
libblockattributes: LibBlockAttributes 0.8.4
libblockattributes_core: LibBlockAttributes (Core) 0.8.5
libblockattributes_fluids: LibBlockAttributes (Fluids) 0.8.5
libblockattributes_items: LibBlockAttributes (Items) 0.8.5
libcd: LibCapableData 3.0.3+1.16.3
libgui: LibGui 3.3.5+1.16.5
library_of_exile: Library of Exile 1.0.6
libstructure: LibStructure 1.5
lightstones: Lightstones 1.3.0
lithium: Lithium 0.6.3
magna: Magna 1.4.3-1.16.2
mcdict: MCDict 2.0.1+1.16.4
megane: megane 3.1.3+1.16.5
megane-api: megane-api 3.1.3+1.16.5
megane-impl: megane-impl 3.1.3+1.16.5
megane-runtime: megane-runtime 3.1.3+1.16.5
minecraft: Minecraft 1.16.5
mm: Manningham Mills 2.1
mo_glass: Mo Glass 1.5-MC1.16.5
modern_industrialization: Modern Industrialization 0.3.12
mostructures: Mo' Structures 1.0.1+mc.1.16.4
multi_item_lib: Multi Item Lib 1.1.1
netherite_plus: Netherite Plus Mod 1.3.17-1.16.5
nourish: Nourish 1.2.1
org_codehaus_groovy_groovy: groovy 3.0.3
org_codehaus_groovy_groovy-jsr223: groovy-jsr223 3.0.3
org_jetbrains_annotations: annotations 20.0.0
org_jetbrains_kotlin_kotlin-reflect: kotlin-reflect 1.4.21
org_jetbrains_kotlin_kotlin-stdlib: kotlin-stdlib 1.4.21
org_jetbrains_kotlin_kotlin-stdlib-jdk7: kotlin-stdlib-jdk7 1.4.21
org_jetbrains_kotlin_kotlin-stdlib-jdk8: kotlin-stdlib-jdk8 1.4.21
org_jetbrains_kotlinx_kotlinx-coroutines-core-jvm: kotlinx-coroutines-core-jvm 1.4.2
org_jetbrains_kotlinx_kotlinx-coroutines-jdk8: kotlinx-coroutines-jdk8 1.4.2
oro_config: OroArmor Config 1.2.0
packages: Packages 1.1.1
patchouli: Patchouli 1.16.4-50-FABRIC
phosphor: Phosphor 0.7.1+build.11
player_roles: Player Roles 1.3.0
playerabilitylib: Pal 1.2.1
polymorph: Polymorph 0.0.7-1.16.4
qcommon-cfg-core: qcommon-cfg-core 3.2.0
qcommon-croco: Croco 2.1.1
quickshulker: Quick Shulker 1.1.14-1.16
reach-entity-attributes: Reach Entity Attribute 1.0.1
reborncore: Reborn Core 4.7.1+build.129
repurposed_structures: Repurposed Structures 1.16.5-1.8.1
reroll: Reroll 1.2.0-1.16.5
respawnablepets: Respawnable Pets 1.16.5-1
rhino: Rhino 1.7.13-build.14
riverredux: River Redux 0.1.6
roughlyenoughitems: Roughly Enough Items 5.10.181
roughlyenoughitems-api: REI (API) 5.10.181
roughlyenoughitems-default-plugin: REI (Default Plugin) 5.10.181
roughlyenoughitems-runtime: REI (Runtime) 5.10.181
roughlyenoughresources: Roughly Enough Resources 2.1.3
rswires: RSWires 4.10.2
rtree-3i-lite-fabric: rtree-3i-lite for Fabric 0.3.0
runelic: Runelic 1.0.2
sandwichable: Sandwichable 1.2-beta5
savemystronghold: Save My Stronghold! 1.16.4-1.0
secretrooms: Secret Rooms 0.9.3+1.16.5
shulkerboxtooltip: Shulker Box Tooltip 2.3.5+1.16.5
shulkerutils: shulkerutils 1.0.1-1.16
simpleteleporters: Simple Teleporters 2.2.1
simplexterrain: Simplex Terrain 0.7.2
smootherbedrock: Smoother Bedrock 1.0.0
someforgepatchesported: Some Forge Patches Ported 1.0.0
special-circumstances: Special Circumstances 1.8.218
staffofbuilding: Staff of Building 1.2.5-1.16.5
static-content: Static Content 1.0.1-1.16.2
staticdata: Static Data 1.1.2
step-height-entity-attribute: Step Height Entity Attribute 1.0.0
stonecutter-tweaks: Stonecutter Tweaks 1.1.0-1.16
strawdummy: Straw Dummy 1.4.0
structure-helpers: Structure Helpers 3.0.0
structurized: Structurized 1.1.0
survivalisland: Survival Island 0.1.5
tacocraft: TacoCraft 1.3.1+mc.1.16
team_reborn_energy: Energy 0.1.1
techreborn: Tech Reborn 3.8.0+build.205
terraform-biome-builder-api-v1: Terraform Biome Builder API (v1) 1.0.4
terraform-config-api-v1: Terraform Config API (v1) 1.0.3
terraform-dirt-api-v1: Terraform Dirt API (v1) 1.1.3
terraform-overworld-biome-extensions-api-v1: Terraform Overworld Biome Extensions API (v1) 1.0.3
terraform-shapes-api-v1: Terraform Shapes API (v1) 1.0.3
terraform-surfaces-api-v1: Terraform Surfaces API (v1) 1.0.3
terraform-tree-api-v1: Terraform Tree API (v1) 1.0.4
terraform-wood-api-v1: Terraform Wood API (v1) 1.0.3
terrestria: Terrestria 2.2.0
tis3d: TIS-3D 1.6.1
tis3d-additions: TIS-3D Additions 0.2.1+1.16.2
tk_valoeghese_zoesteriaconfig: ZoesteriaConfig 1.3.2
totemmod: Wither Totems Mod 0.3.2
trapexpansion: Trap Expansion 1.3.2
traverse: Traverse 3.3.1
trinkets: Trinkets 2.6.7
truerooms: True Secret Rooms 1.1.3
vanilla-hammers: Vanilla Hammers 3.0.1-1.16.3
vanilladeathchest: VanillaDeathChest 1.16.3-1.11.0.7-fabric
vanillaexcavators: Vanilla Excavators 1.1.0
villagerhats: Villager Hats fabric-1.16.4-1.0.1
voyager: Voyager 1.0.0
waystones: Waystones 1.1.1.1
wild_explorer: Wild Explorer 1.3.2
winged: Winged Mod 1.16.2-1.4.1
wolveswitharmor: Wolves With Armor 1.5.2-1.16.2
woodenhoppers: Wooden Hoppers 1.0.0
woods_and_mires: Woods and Mires 1.0.4+1.16.3
wthit: wthit 2.2.1+1.16.5
yosbr: YOSBR 0.1.1
yungsapi: YUNG's API 1.16.4-Fabric-1
Player Count: 2 / 5; [class_3222['Tronto1899'/37500, l='ServerLevel[world]', x=-252.19, y=71.00, z=-34.04], class_3222['cavayero'/79429, l='ServerLevel[world]', x=-251.27, y=71.00, z=-35.52]]
Data Packs: vanilla (incompatible), Fabric Mods, null
Is Modded: Definitely; Server brand changed to 'fabric'
Type: Dedicated Server (map_server.txt)

the problem was successfully solved: I check two options, both solve the issue: Update modpack to 2.6.8/9 or just single upgrade VanillaDeathChest to version 2.0.5.