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# tableView(_:mouseDownInHeaderOf:)

Tells the delegate that the mouse button was clicked in the specified table column’s header.

```
@MainActor optional func tableView(_ tableView: NSTableView, mouseDownInHeaderOf tableColumn: NSTableColumn)
```

## Parameters

`tableView`

The table view that sent the message.

`tableColumn`

The table column.

## Discussion

---

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