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# WKWebExtension.Error

Constants that indicate errors in the [`WKWebExtension`](/documentation/WebKit/WKWebExtension) domain.

```
struct Error
```

## Topics

### Type Properties

[`static var errorDomain: String`](/documentation/WebKit/WKWebExtension/Error/errorDomain)

[`static var invalidArchive: WKWebExtension.Error.Code`](/documentation/WebKit/WKWebExtension/Error/invalidArchive)

Indicates that the archive file is invalid or corrupt.

[`static var invalidBackgroundPersistence: WKWebExtension.Error.Code`](/documentation/WebKit/WKWebExtension/Error/invalidBackgroundPersistence)

Indicates that the extension specified background persistence that was not compatible with the platform or features requested.

[`static var invalidDeclarativeNetRequestEntry: WKWebExtension.Error.Code`](/documentation/WebKit/WKWebExtension/Error/invalidDeclarativeNetRequestEntry)

Indicates that an invalid declarative net request entry was encountered.

[`static var invalidManifest: WKWebExtension.Error.Code`](/documentation/WebKit/WKWebExtension/Error/invalidManifest)

Indicates that an invalid `manifest.json` was encountered.

[`static var invalidManifestEntry: WKWebExtension.Error.Code`](/documentation/WebKit/WKWebExtension/Error/invalidManifestEntry)

Indicates that an invalid manifest entry was encountered.

[`static var invalidResourceCodeSignature: WKWebExtension.Error.Code`](/documentation/WebKit/WKWebExtension/Error/invalidResourceCodeSignature)

Indicates that a resource failed the bundle’s code signature checks.

[`static var resourceNotFound: WKWebExtension.Error.Code`](/documentation/WebKit/WKWebExtension/Error/resourceNotFound)

Indicates that a specified resource was not found on disk.

[`static var unknown: WKWebExtension.Error.Code`](/documentation/WebKit/WKWebExtension/Error/unknown)

Indicates that an unknown error occurred.

[`static var unsupportedManifestVersion: WKWebExtension.Error.Code`](/documentation/WebKit/WKWebExtension/Error/unsupportedManifestVersion)

Indicates that the manifest version is not supported.

## Relationships

### Conforms To

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`CustomNSError`](/documentation/Foundation/CustomNSError)

[`Hashable`](/documentation/Swift/Hashable)

[`Sendable`](/documentation/Swift/Sendable)

[`Equatable`](/documentation/Swift/Equatable)

[`Error`](/documentation/Swift/Error)

---

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