After updating tModLoader to version v2024.3.3.3 I started having crashes when hosting a multiplayer game with my world. The log suggests that this mod causes the problem:

[00:10:13.575] [23/ERROR] [tML]: Unhandled Exception
System.InvalidOperationException: Collection was modified; enumeration operation may not execute.
at System.Collections.Generic.Dictionary`2.Enumerator.MoveNext()
at WWeaponScaling.Items.globalItem.SetDefaults(Item item) in WWeaponScaling\Items\globalItem.cs:line 47
at Terraria.ModLoader.Core.GlobalLoaderUtils`2.SetDefaultsBeforeLookupsAreBuilt(TEntity entity, TGlobal[] entityGlobals, Action`1 setModEntityDefaults, InstantiationTime[]& instTimes) in tModLoader\Terraria\ModLoader\Core\GlobalLoaderUtils.cs:line 89
at Terraria.ModLoader.Core.GlobalLoaderUtils`2.SetDefaultsBeforeLookupsAreBuilt(TEntity entity, TGlobal[] entityGlobals, Action`1 setModEntityDefaults) in tModLoader\Terraria\ModLoader\Core\GlobalLoaderUtils.cs:line 63
at Terraria.ModLoader.Core.GlobalLoaderUtils`2.SetDefaults(TEntity entity, TGlobal[]& entityGlobals, Action`1 setModEntityDefaults) in tModLoader\Terraria\ModLoader\Core\GlobalLoaderUtils.cs:line 29
at Terraria.Item.SetDefaults(Int32 Type, Boolean noMatCheck, ItemVariant variant) in tModLoader\Terraria\Item.cs:line 48460
at Terraria.Item..ctor(Int32 setDefaultsToType, Int32 stack, Int32 prefix) in tModLoader\Terraria\Item.cs:line 758
at ImproveGame.Content.Functions.Construction.MaterialCore.<>c.<PostSetupContent>b__25_0() in ImproveGame\Content\Functions\Construction\MaterialCore.cs:line 92
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)

Here's an archive with the logs and the world:
https://0x0.st/XPQs.zip