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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.
Steps to reproduce:
1. Create new Unity project
2. Open Package Manager
3. Create a new Package
4. Select to edit new Package Manifest in Inspector
5. In Inspector, Dependencies press “+” to add multiple packages with versions
6. Press “Apply”
7. Observe the Console window
Actual results: Error is thrown: “ArgumentException: An item with the same key has already been added. Key: com.unity.test-framework
System.Collections.Generic.Dictionary`2[TKey,TValue].TryInsert (TKey key, TValue value, System.Collections.Generic.InsertionBehavior behavior) (at <c818795a2e354f2faac5f8cee1240e70>:0)
System.Collections.Generic.Dictionary`2[TKey,TValue].Add (TKey key, TValue value) (at <c818795a2e354f2faac5f8cee1240e70>:0)
UnityEditor.PackageManager.UI.Internal.PackageManifestImporterEditor.WritePackageManifest (UnityEngine.Object target, UnityEditor.PackageManager.UI.Internal.PackageManifestImporterEditor+PackageManifestState packageState) (at /Users/bokken/build/output/unity/unity/Modules/PackageManagerUI/Editor/UI/PackageManifestImporterEditor.cs:829)”
Expected results: Adding a package with the same name and version should not be allowed, “Apply” button should be greyed out
Reproducible with versions: 6000.3.5f1, 6000.4.0b5, 6000.5.0a5
Can’t test with versions: 6000.0.66f1 (no such functionality)
Tested on (OS): macOS Silicon Tahoe 26.2 (M1)
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