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Thank you for reporting a bug to Unity. We have reviewed the issue carefully, and in this case, the team is unable to prioritize fixing this bug. There are a number of reasons we make this decision, including the impact and severity of the issue across our user and customer base, and the possibility that future plans may solve the problem in a different way, or that a workaround for the bug may be available. Today we will be closing this case. Thank you again for taking the time to report this issue, and please let us know if there is anything else that changes the impact or severity of this issue.
Thank you for reporting a bug to Unity. We have reviewed the issue carefully, and in this case, the team is unable to prioritize fixing this bug. There are a number of reasons we make this decision, including the impact and severity of the issue across our user and customer base, and the possibility that future plans may solve the problem in a different way, or that a workaround for the bug may be available. Today we will be closing this case. Thank you again for taking the time to report this issue, and please let us know if there is anything else that changes the impact or severity of this issue.
Thank you for reporting a bug to Unity. We have reviewed the issue carefully, and in this case, the team is unable to prioritize fixing this bug. There are a number of reasons we make this decision, including the impact and severity of the issue across our user and customer base, and the possibility that future plans may solve the problem in a different way, or that a workaround for the bug may be available. Today we will be closing this case. Thank you again for taking the time to report this issue, and please let us know if there is anything else that changes the impact or severity of this issue.
Reproduction steps:
1. Create a new project
2. Install Multiplayer Play Mode package (Window > Package Management > Package Manager)
3. Open Play Mode Scenarios window (Window > Play Mode > Scenarios), add a new Scenario and an Additional Editor Instance
4. Select the newly created Scenario as the active Scenario and enter Play mode
5. Enable Hierarchy in the Player 2 window Layout dropdown
6. Create Tree GameObject in the Player 2 Hierarchy (right-click > 3D Object > Tree)
7. Observe the Console
Actual result: "ArgumentNullException: Value cannot be null. Parameter name: sameAssetFile" error is thrown
Expected result: No errors or warnings are thrown
Reproducible with: 1.6.3 (6000.0.80f1), 2.0.2 (6000.3.20f1, 6000.5.6f1), 3.0.0 (6000.6.0b6, 6000.7.0a3)
Reproduced on: Windows 11, macOS Tahoe 26.5 (M4)
Note:
Full error:
ArgumentNullException: Value cannot be null. Parameter name: sameAssetFile UnityEditor.AssetDatabase.AddObjectToAsset_Obj (UnityEngine.Object newAsset, UnityEngine.Object sameAssetFile) (at <b9860ef9ab5e43a4a09be932a4cd5645>:0) UnityEditor.AssetDatabase.AddObjectToAsset (UnityEngine.Object objectToAdd, UnityEngine.Object assetObject) (at /Users/bokken/build/output/unity/unity/Modules/AssetDatabase/Editor/ScriptBindings/AssetDatabase.bindings.cs:387) TreeEditor.TreeEditor.CreateNewTree (UnityEditor.MenuCommand menuCommand) (at /Users/bokken/build/output/unity/unity/Modules/TreeEditor/TreeEditor.cs:334) UnityEditor.MenuUtils:MenuCallback(Object) Unity.Hierarchy.Editor.<>c__DisplayClass0_0:<AppendFromGenericMenu>b__0(DropdownMenuAction) (at /Users/bokken/build/output/unity/unity/Modules/HierarchyEditor/Managed/DropdownMenuHelper.cs:23) UnityEditor.GenericMenu:CatchMenu(Object, String[], Int32) (at /Users/bokken/build/output/unity/unity/Editor/Mono/GUI/GenericMenu.cs:164)
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