Native print preview doesn't render - UIPrintInteractionController Swift 4.0

We want to print html in WKWebView with this method.

            printController.delegate = self let formatter = UIMarkupTextPrintFormatter(markupText: htmlString) printController.printFormatter = formatter

However, the print options pop up screen remains gray. HTML does not load. How can we catch the exception here? Is there any error handling delegate method for UIPrintInteractionController ?