myCode is here // titleScript = "document.querySelector('#\(rawValue) span')?.textContent" guard let titleResult = try? await webView.evaluateJavaScript(type.titleScript), let title = titleResult as? String else { return } this code has error Thread 1: Swift runtime failure: Unexpectedly found nil while implicitly unwrapping an Optional value but edit Code like this It is works Successful do { ... let titleResult = try await webView.evaluateJavaScript(type.titleScript) let title = titleResult as? String ... } catch { LogManager.log(level: .error, self, #function, error, "title is Invalid : \(type.titleScript)") continue } I don't know why guard let _ = try? is Fail