iOS 26 beta - Apply prominentGlass to button shows default font

Use setAttributedTitle to set the title of the button, including any relevant formatting information. For example:

class ViewController: UIViewController {
  private let button: UIButton = {
    let button = UIButton(configuration: .prominentGlass())
    button.translatesAutoresizingMaskIntoConstraints = false
    if let attrFont = UIFont(name: "Helvetica", size: 40) {
      let attrTitle = NSAttributedString(string: "Hello world", attributes: [NSAttributedString.Key.font: attrFont])
      button.setAttributedTitle(attrTitle, for: UIControl.State.normal)
   }
    return button
  }()
   
  override func viewDidLoad() {
    super.viewDidLoad()
    view.addSubview(button)
    NSLayoutConstraint.activate([
      button.centerXAnchor.constraint(equalTo: view.centerXAnchor),
      button.centerYAnchor.constraint(equalTo: view.centerYAnchor),
    ])
    button.addTarget(self, action: #selector(buttonTapped), for: .touchUpInside)
  }
   
  @objc private func buttonTapped() {
    print("Button tapped!")
  }
}