In an Xcode 26.4 + iOS 26.x environment, I called evaluateJavaScript inside webView(_ webView: WKWebView, didCommit navigation: WKNavigation!) and got the following error: Printing description of error: ▿ Optional<Error> - some : Error Domain=WKErrorDomain Code=4 "A JavaScript exception occurred" UserInfo={WKJavaScriptExceptionLineNumber=0, WKJavaScriptExceptionMessage=TypeError: undefined is not a function, WKJavaScriptExceptionColumnNumber=0, NSLocalizedDescription=A JavaScript exception occurred}) However, this worked fine in earlier versions before Xcode 26.4 (> 26.0 and < 26.4, though I do not remember the exact version), still with iOS 26.x. It also works fine in an Xcode 26.4 + iOS 18.x environment. And if I add a slight delay using DispatchQueue.main.asyncAfter in the Xcode 26.4 + iOS 26.x environment, then it works without any issue. So what exactly is going on here? I would really appreciate an explanation.