UDSFilesystem read handle errors are thrown and assets fail to import when creating a project from a custom template via Hub

Steps to reproduce:

1. Create a new project using 3D URP template
2. Wait for the Editor to finish importing, then close it
3. In Unity Hub, find the created project
4. Click on the three dots > Save project as custom template
5. Enter description and leave other settings as is
6. Create the template
7. In Hub click "+ New Project"
8. Create a new project using same Editor version and that custom template
9. Observe the Console in the newly created project

Actual results: The Console fills with hundreds of UDSFilesystem asset loading errors, some assets fail to import, and the render pipeline fails to initialize

Expected results: The project created from the custom template opens with no Console errors, all assets import successfully

Reproducible with versions: 3.21.0 (6000.6.0a4, 6000.6.0b10, 6000.7.0a5)

Not reproducible with versions: 3.21.0 (6000.5.10f1, 6000.6.0a3)

Tested on (OS): Ubuntu 24.04, macOS 26.5

Notes:

• Errors are clearable but reappear when entering Play mode or trying to build the project
• Deleting the Library folder resolves the errors
• Six ShaderGraph assets fail to import, so they are missing from the created project: 0_Particle Unlit, 1_Decal Material Volume, 2_Particle Lit, UGUI Canvas Basic, UGUI Canvas Meter, and Terrain Standard 4 Layers URP
• The Editor's artifact storage moved from Library/Artifacts to Library/DataStore in 6000.6.0a4 via PR #93651, matching the version boundary above

 

Some of the errors:

• Invalid read handle
• UDSFilesystem failed to acquire a read handle for hash uds:/4e/4e99f8ce3f0f141998cc404465118e22
• Error loading the file VirtualArtifacts/Primary/e079a17a0b2b93647a84cebdde8f3c21'. File is either empty or corrupted, please verify the file contents.
• Host type is not matching any asset type at Path Packages/com.unity.render-pipelines.universal/Shaders/Utils/CopyDepth.shader.
• Asset import failed, "Packages/com.unity.shadergraph/GraphTemplates/Cross Pipeline/2_Particle Lit.shadergraph" > NullReferenceException: Object reference not set to an instance of an object
• Cannot create required material because shader is null
• Cannot initialize a LocalKeyword with a null Shader
• MissingReferenceException: The object of type 'UnityEngine.Shader' has been destroyed but you are still trying to access it