NSForegroundColorAttributeName doesn't work any more

Cocoa Programming for OS X (5th Edition) 16. Using Notifications
2

NSMutableAttributedString.addAttribute

func addAttribute (_ name: NSAttributedStringKey, value: Any, range: NSRange)

NSAttributedStringKey is defined as a struct with static members; one of them is foregroundColor.

override func viewDidLayout() {
    print (#function)
    
    let text = "Hoot, Hoot!"
    var fancyText = NSMutableAttributedString (string: text)
    fancyText.addAttribute (NSAttributedStringKey.foregroundColor, value:NSColor.red, range:NSRange (location:0, length:fancyText.length))
    
    outletTextView.insertText (fancyText, replacementRange: NSRange (location:0, length:0))
}