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# WKWebExtension.MessagePort

An object that manages message-based communication with a web extension.

```
@MainActor class MessagePort
```

## Overview

Contains properties and methods to handle message exchanges with a web extension.

## Topics

### Errors

[`WKWebExtension.MessagePort.Error.Code`](/documentation/WebKit/WKWebExtension/MessagePort/Error/Code)

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

[`errorDomain`](/documentation/WebKit/WKWebExtension/MessagePort/errorDomain)

A string that identifies the error domain.


---

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