Implement Custom ViewController using custom WKWebViewConfiguration

I would like to implement a default custom SubClass of WKWebview as mentioned here:

The guide is working well and I can see the app using my CustomViewController.
Now I would like to change the properties of the WKWebViewConfiguration,

This is failing and I am wondering, if there is a working example or implementation guide here.

this is how far I got:

//  MyViewController.swift
//  App

import UIKit
import Capacitor

class MyViewController: CAPBridgeViewController {

    override func viewDidLoad() {
        // Do any additional setup after loading the view.
        print("MyViewController instance created.")
        let webViewConfiguration = WKWebViewConfiguration()
        // Add the custom web view as a subview
        let customWebView = CustomWKWebView(frame: .zero, configuration: webViewConfiguration)
        webViewConfiguration.setURLSchemeHandler(CustomRequestInterceptor(), forURLScheme: "customScheme")

    override func instanceDescriptor() -> InstanceDescriptor {
        let descriptor = super.instanceDescriptor()
        // add custom settings here
        return descriptor


//  CustomRequestInterceptor.swift
//  App

import WebKit

class CustomRequestInterceptor: NSObject, WKURLSchemeHandler {
    func webView(_ webView: WKWebView, start urlSchemeTask: WKURLSchemeTask) {
        // Intercept and modify the request here
        print("CustomRequestInterceptor instance created")
        var request = urlSchemeTask.request
        print("CustomRequestInterceptor request", request)
        if let url = request.url, url.scheme == "customScheme" || url.scheme == "https" {
            // Add your cookie header here
            print("CustomRequestInterceptor url", url)
            if var headers = request.allHTTPHeaderFields {
                headers["Cookie"] = "your-cookie-data-here"
                request.allHTTPHeaderFields = headers
            // You need to create a response and call didReceiveResponse
            let response = HTTPURLResponse(url: url, statusCode: 200, httpVersion: "HTTP/1.1", headerFields: nil)!
            // urlSchemeTask.didReceive(urlSchemeTask.request)
            // You should also call urlSchemeTask.didFinish() once the task is completed
        } else {
            // Handle errors if necessary
            urlSchemeTask.didFailWithError(NSError(domain: NSURLErrorDomain, code: NSURLErrorBadURL, userInfo: nil))

    func webView(_ webView: WKWebView, stop urlSchemeTask: WKURLSchemeTask) {
        // Handle cleanup if necessary

Within the capacitor application I have some URLs which want to request


I would expect to have a log with
“CustomRequestInterceptor instance created” but this does not appear.

Is there a recommended implementation for changing the WKWebViewConfiguration for Capacitors Webview?