window.webkit.messageHandlers is null on ios 15

Question

window.webkit.messageHandlers gives null on ios 15, but when I set config.limitsNavigationsToAppBoundDomains = true; it works properly.

But I don't want to restrict my WkWebView to certain domains.

Code -

let config = WKWebViewConfiguration()
    config.preferences.javaScriptEnabled = true
    let userContentController = WKUserContentController()

    userContentController.add(WKSMH, name: "print")
    userContentController.add(WKSMH, name: "push-subscribe")
    userContentController.add(WKSMH, name: "push-permission-request")
    userContentController.add(WKSMH, name: "push-permission-state")
    userContentController.add(WKSMH, name: "setUserAttribute")
    config.userContentController = userContentController
    if #available(iOS 14, *) {
        config.limitsNavigationsToAppBoundDomains = true;
    }
    config.preferences.javaScriptCanOpenWindowsAutomatically = true
    config.allowsInlineMediaPlayback = true
    config.preferences.setValue(true, forKey: "standalone")
    
    let webView = WKWebView(frame: calcWebviewFrame(webviewView: container, toolbarView: nil), configuration: config)

Is there any way to use messageHandlers other than using config.limitsNavigationsToAppBoundDomains = true ?