WebAssembly and @MainActor – nothing runs

Platform Swift for WebAssembly
10 
swiftc -version
Apple Swift version 6.2-dev (LLVM 8e19caa07d62341, Swift bf2671510d1631a)
Target: arm64-apple-macosx26.0
Build config: +assertions

swiftc -print-target-info

{
  "compilerVersion": "Apple Swift version 6.2-dev (LLVM 8e19caa07d62341, Swift bf2671510d1631a)",
  "swiftCompilerTag": "swift-6.2-DEVELOPMENT-SNAPSHOT-2025-10-09-a",
  "target": {
    "triple": "arm64-apple-macosx26.0",
    "unversionedTriple": "arm64-apple-macosx",
    "moduleTriple": "arm64-apple-macos",
    "platform": "macosx",
    "arch": "arm64",
    "pointerWidthInBits": 64,
    "pointerWidthInBytes": 8,
    "swiftRuntimeCompatibilityVersion": "6.2",
    "compatibilityLibraries": [ ],
    "openbsdBTCFIEnabled": false,
    "librariesRequireRPath": false
  },
  "paths": {
    "runtimeLibraryPaths": [
      "~/Library/Developer/Toolchains/swift-6.2-DEVELOPMENT-SNAPSHOT-2025-10-09-a.xctoolchain/usr/lib/swift/macosx",
      "/usr/lib/swift"
    ],
    "runtimeLibraryImportPaths": [
      "~/Library/Developer/Toolchains/swift-6.2-DEVELOPMENT-SNAPSHOT-2025-10-09-a.xctoolchain/usr/lib/swift/macosx"
    ],
    "runtimeResourcePath": "~/Library/Developer/Toolchains/swift-6.2-DEVELOPMENT-SNAPSHOT-2025-10-09-a.xctoolchain/usr/lib/swift"
  }
}