libsbsario_connector.dylib fails to load on macOS with "library load disallowed by system policy" error in Unity.

Problem Summary:

On macOS, the Substance3D for Unity plugin fails to load due to code signing and notarization issues with the libsbsario_connector.dylib native library. Users encounter both a Gatekeeper warning dialog and a System.DllNotFoundException in the Unity console.

Error Messages:

1. Gatekeeper Dialog:
   "libsbsario_connector.dylib" couldn't be opened because Apple cannot check it for malicious software.
2. Console Error:
   System.DllNotFoundException: dlopen(...libsbsario_connector.dylib, 0x0002): tried: '...' (code signature in <48C06BDC-5FB4-34F6-A868-B9C6BA6AFBA4> '...' not valid for use in process: library load disallowed by system policy)

Root Cause:

The dylib lacks either a valid Apple Developer ID code signature or Apple Notarization approval (required for all macOS software downloaded over the network). The error message "code signature... not valid for use in process" indicates a signature exists but is invalid for runtime use on current macOS versions.

Steps to Reproduce:

1. Install Substance3D for Unity (latest version) from the Asset Store on macOS (Sonoma or Sequoia)
2. Create or open a Unity project that includes the plugin
3. Launch Unity Editor
4. Observe: Gatekeeper warning dialog appears
5. Check Unity Console: System.DllNotFoundException with "library load disallowed by system policy"

Affected Versions:

• macOS: Tahoe 26.5.2
• Unity: 6000.3.10f1
• Substance3D for Unity: Latest version from Asset Store
• Architecture: Apple Silicon (arm64)

Temporary Workaround:

The issue can be temporarily mitigated (but not properly fixed) with:

xattr -dr com.apple.quarantine "/path/to/Assets/Adobe/Substance3DForUnity"
codesign --force --deep --sign - "/path/to/Assets/Adobe/Substance3DForUnity"

Expected Resolution:

Adobe should:

1. Code-sign all native binaries with a valid Apple Developer ID certificate
2. Submit for Apple Notarization approval
3. Re-distribute the corrected plugin through the Asset Store