Game crashes when saving item assembly with a period at the end of the name

[raymen101]

Disclaimers

• I have searched the issue tracker to check if the issue has already been reported.
• My issue happened while using mods.

What happened?

title says it all.

instant crash when saving item assembly when the name ends with a period.

a folder is created in LocalMods with a filelist.xml, but no actual assembly .xml

Reproduction steps

open submarine editor
place an item
"save as item assembly"
name it "test."
save -> crash

Bug prevalence

Happens every now and then

Single player or multiplayer?

Other

-

In sub editor menus

Version

v1.12.6.2 (Spring Update 2026)

-

No response

Which operating system did you encounter this bug on?

Windows

Relevant error messages and crash reports

Barotrauma Client crash report (generated on 05/17/2026 17:29:59)

Barotrauma seems to have crashed. Sorry for the inconvenience! 

7D2095381925120657119302C1CBA568

Game version 1.12.7.0 (ReleaseWindows, branch master, revision 8d90ccb)
Graphics mode: 2560x1440 (BorderlessWindowed)
VSync ON
Language: English
Selected content packages: Vanilla (D54FDC7), Playground (99E98F1), SafetyAutoDoor (7D9043B), Bulkhead Door (481720F), MedBed (CCDCEDA), medbedDouble (762C970), shuttle shell parts (C25BB8A), shuttle glass parts (01A04A9), shells (BDEAD22), Orca2 in Layers (3E5BF47), Smooth Charger (6E975EC), 1500K Emergency Light (5E45CD0), BallastCleanoutControls (414D550), 3000K Lamp (4448E54), DivingSuitLockerWPower (FA4EF50), HatchNice (465BBAF), Ball o Death (86241EC), Test Platform (7B601ED), Averager (748F408), Bulkhead Door 2.1 (0339E2E), Airlock Smooth 1.0 (B4D2CCB), Airlock Fast V1.1 (269F757), Hatch Nice 1.1 (EEFF917), Amsel (9A55051), Amsel V1.6 (43559BE), BulkHead WindowedDoor 2.1 (13B8DC1), Amsel V1.7.1 (173C030), ABS v1.1 (8E2A4AE), P.A.W.S v1.0 (3F3C22E), Reactor control V1.0 (80E4B45), P.A.W.S. V1.1 (11D007E), P.A.W.S V1.1 (63D708E)
Level seed: no level loaded
Loaded submarine: A Test Platform (85FD8B7AFC7903387C14F6C3280F8A08)
Selected screen: Barotrauma.SubEditorScreen
SteamManager initialized

System info:
    Operating system: Microsoft Windows NT 10.0.19045.0 64 bit
    GPU name: NVIDIA GeForce RTX 3070
    Display mode: {Width:2560 Height:1440 Format:Color AspectRatio:1.7777778}
    GPU status: Normal

Exception: Sequence contains no matching element (System.InvalidOperationException)
Target site: Void ThrowNoMatchException()
Stack trace: 
   at System.Linq.ThrowHelper.ThrowNoMatchException()
   at System.Linq.Enumerable.First[TSource](IEnumerable`1 source, Func`2 predicate)
   at Barotrauma.ContentPackageManager.PackageSource.GetRegularModByPath(String fileListPath) in <DEV>/Barotrauma/BarotraumaClient/ClientSource/ContentManagement/ContentPackageManager.cs:line 29
   at Barotrauma.SubEditorScreen.<>c__DisplayClass145_0.<SaveAssembly>g__Save|0() in <DEV>/Barotrauma/BarotraumaClient/ClientSource/Screens/SubEditorScreen.cs:line 3614
   at Barotrauma.SubEditorScreen.SaveAssembly(GUIButton button, Object obj) in <DEV>/Barotrauma/BarotraumaClient/ClientSource/Screens/SubEditorScreen.cs:line 3601
   at Barotrauma.GUIButton.Update(Single deltaTime) in <DEV>/Barotrauma/BarotraumaClient/ClientSource/GUI/GUIButton.cs:line 299
   at Barotrauma.GUI.Update(Single deltaTime) in <DEV>/Barotrauma/BarotraumaClient/ClientSource/GUI/GUI.cs:line 1298
   at Barotrauma.GameMain.Update(GameTime gameTime) in <DEV>/Barotrauma/BarotraumaClient/ClientSource/GameMain.cs:line 1019
   at Microsoft.Xna.Framework.Game.Tick() in E:\Barotrauma-development\Libraries\MonoGame.Framework\Src\MonoGame.Framework\Game.cs:line 500
   at Microsoft.Xna.Framework.SdlGamePlatform.RunLoop() in E:\Barotrauma-development\Libraries\MonoGame.Framework\Src\MonoGame.Framework\SDL\SDLGamePlatform.cs:line 94
   at Microsoft.Xna.Framework.Game.Run(GameRunBehavior runBehavior) in E:\Barotrauma-development\Libraries\MonoGame.Framework\Src\MonoGame.Framework\Game.cs:line 397
   at Microsoft.Xna.Framework.Game.Run() in E:\Barotrauma-development\Libraries\MonoGame.Framework\Src\MonoGame.Framework\Game.cs:line 367
   at Barotrauma.Program.Main(String[] args) in <DEV>/Barotrauma/BarotraumaClient/ClientSource/Program.cs:line 61

Last debug messages:
[05/17/2026 17:29:49] [CL] [Lua] - Run LocalMods/LuaCsForBarotrauma/Lua/LuaSetup.lua
[05/17/2026 17:29:49] [CL] [Lua] Executing scripts
[05/17/2026 17:29:49] [CL] LuaCs running state entered. Running under commit 8d90ccb, CSharp is disabled
[05/17/2026 17:29:49] Timeline game mode set to Playing
[05/17/2026 17:28:56] Epic Online Services Result "UnexpectedError" was not handled by "UnlockAchievements".
[05/17/2026 17:28:55] Timeline game mode set to Menus
[05/17/2026 17:28:55] [CL] LuaCs no execution state entered
[05/17/2026 17:28:55] [CL] Services have been reset
[05/17/2026 17:28:55] [CL] LuaCs unloaded state entered
[05/17/2026 17:28:55] [CL] LuaCs running state exited
[05/17/2026 17:27:57] [CL] [Lua] - Run C:/Users/USERNAME/AppData/Local/Daedalic Entertainment GmbH/Barotrauma/WorkshopMods/Installed/2852315967/Lua/Autorun/lualinker.lua
[05/17/2026 17:27:57] [CL] [Lua] - Run C:/Users/USERNAME/AppData/Local/Daedalic Entertainment GmbH/Barotrauma/WorkshopMods/Installed/2852315967/Lua/Autorun/luaDisplaySideBySide.lua
[05/17/2026 17:27:57] [CL] [Lua] - Run LocalMods/LuaCsForBarotrauma/Lua/LuaSetup.lua
[05/17/2026 17:27:57] [CL] [Lua] Executing scripts
[05/17/2026 17:27:57] [CL] LuaCs running state entered. Running under commit 8d90ccb, CSharp is disabled
[05/17/2026 17:27:57] [CL] LuaCs no execution state entered
[05/17/2026 17:27:57] [CL] LuaCs running state exited
[05/17/2026 17:27:57] [CL] [Lua] - Run C:/Users/USERNAME/AppData/Local/Daedalic Entertainment GmbH/Barotrauma/WorkshopMods/Installed/2852315967/Lua/Autorun/lualinker.lua
[05/17/2026 17:27:57] [CL] [Lua] - Run C:/Users/USERNAME/AppData/Local/Daedalic Entertainment GmbH/Barotrauma/WorkshopMods/Installed/2852315967/Lua/Autorun/luaDisplaySideBySide.lua
[05/17/2026 17:27:57] [CL] [Lua] - Run LocalMods/LuaCsForBarotrauma/Lua/LuaSetup.lua
[05/17/2026 17:27:57] [CL] [Lua] Executing scripts
[05/17/2026 17:27:57] [CL] LuaCs running state entered. Running under commit 8d90ccb, CSharp is disabled
[05/17/2026 17:27:57] [CL] LuaCs no execution state entered
[05/17/2026 17:27:57] [CL] LuaCs running state exited
[05/17/2026 17:27:57] [CL] [Lua] - Run C:/Users/USERNAME/AppData/Local/Daedalic Entertainment GmbH/Barotrauma/WorkshopMods/Installed/2852315967/Lua/Autorun/lualinker.lua
[05/17/2026 17:27:57] [CL] [Lua] - Run C:/Users/USERNAME/AppData/Local/Daedalic Entertainment GmbH/Barotrauma/WorkshopMods/Installed/2852315967/Lua/Autorun/luaDisplaySideBySide.lua
[05/17/2026 17:27:57] [CL] [Lua] - Run LocalMods/LuaCsForBarotrauma/Lua/LuaSetup.lua
[05/17/2026 17:27:57] [CL] [Lua] Executing scripts
[05/17/2026 17:27:57] [CL] LuaCs running state entered. Running under commit 8d90ccb, CSharp is disabled
[05/17/2026 17:27:57] [CL] LuaCs no execution state entered
[05/17/2026 17:27:57] [CL] LuaCs running state exited
[05/17/2026 17:25:59] [CL] [Lua] - Run C:/Users/USERNAME/AppData/Local/Daedalic Entertainment GmbH/Barotrauma/WorkshopMods/Installed/2852315967/Lua/Autorun/lualinker.lua
[05/17/2026 17:25:59] [CL] [Lua] - Run C:/Users/USERNAME/AppData/Local/Daedalic Entertainment GmbH/Barotrauma/WorkshopMods/Installed/2852315967/Lua/Autorun/luaDisplaySideBySide.lua
[05/17/2026 17:25:59] [CL] [Lua] - Run LocalMods/LuaCsForBarotrauma/Lua/LuaSetup.lua
[05/17/2026 17:25:59] [CL] [Lua] Executing scripts
[05/17/2026 17:25:59] [CL] LuaCs running state entered. Running under commit 8d90ccb, CSharp is disabled
[05/17/2026 17:25:58] Timeline game mode set to Playing
[05/17/2026 17:25:56] Timeline game mode set to Menus
[05/17/2026 17:25:13] Epic Online Services Result "UnexpectedError" was not handled by "UnlockAchievements".
[05/17/2026 17:25:13] [CL] LuaCs no execution state entered
[05/17/2026 17:25:01] Attempting to open ALC device "OpenAL Soft on Headphones (OpenRun Pro by Shokz Stereo)"
[05/17/2026 17:24:57] Logged in as Raven (SteamID STEAM_1:0:78328265)