diff --git a/src/main/java/org/htmlunit/javascript/JavaScriptEngine.java b/src/main/java/org/htmlunit/javascript/JavaScriptEngine.java
index e23266cd17..a161357202 100644
--- a/src/main/java/org/htmlunit/javascript/JavaScriptEngine.java
+++ b/src/main/java/org/htmlunit/javascript/JavaScriptEngine.java
@@ -82,6 +82,7 @@
 import org.htmlunit.javascript.host.Window;
 import org.htmlunit.javascript.host.WindowOrWorkerGlobalScope;
 import org.htmlunit.javascript.host.dom.DOMException;
+import org.htmlunit.javascript.host.fetch.Headers;
 import org.htmlunit.javascript.host.html.HTMLElement;
 import org.htmlunit.javascript.host.html.HTMLImageElement;
 import org.htmlunit.javascript.host.html.HTMLOptionElement;
@@ -248,6 +249,7 @@ private void init(final WebWindow webWindow, final Page page, final Context cx)
         // TODO remove the cast
         URLSearchParams.NativeParamsIterator.init(scope, "URLSearchParams Iterator");
         FormData.FormDataIterator.init(scope, "FormData Iterator");
+        Headers.NativeHeadersIterator.init(scope, "Headers Iterator");
 
         // strange but this is the reality for browsers
         // because there will be still some sites using this for browser detection the property is
diff --git a/src/main/java/org/htmlunit/javascript/host/Window.java b/src/main/java/org/htmlunit/javascript/host/Window.java
index 25e28dc1c9..91f42c4e2c 100644
--- a/src/main/java/org/htmlunit/javascript/host/Window.java
+++ b/src/main/java/org/htmlunit/javascript/host/Window.java
@@ -52,6 +52,8 @@
 import org.htmlunit.TopLevelWindow;
 import org.htmlunit.WebAssert;
 import org.htmlunit.WebClient;
+import org.htmlunit.WebRequest;
+import org.htmlunit.WebResponse;
 import org.htmlunit.WebConsole;
 import org.htmlunit.WebWindow;
 import org.htmlunit.WebWindowNotFoundException;
@@ -61,6 +63,7 @@
 import org.htmlunit.corejs.javascript.Function;
 import org.htmlunit.corejs.javascript.JavaScriptException;
 import org.htmlunit.corejs.javascript.NativeConsole.Level;
+import org.htmlunit.corejs.javascript.NativePromise;
 import org.htmlunit.corejs.javascript.NativeObject;
 import org.htmlunit.corejs.javascript.Scriptable;
 import org.htmlunit.corejs.javascript.ScriptableObject;
@@ -110,6 +113,8 @@
 import org.htmlunit.javascript.host.event.MessageEvent;
 import org.htmlunit.javascript.host.event.MouseEvent;
 import org.htmlunit.javascript.host.event.UIEvent;
+import org.htmlunit.javascript.host.fetch.Request;
+import org.htmlunit.javascript.host.fetch.Response;
 import org.htmlunit.javascript.host.html.DocumentProxy;
 import org.htmlunit.javascript.host.html.HTMLCollection;
 import org.htmlunit.javascript.host.html.HTMLDocument;
@@ -304,6 +309,40 @@ public String atob(final String encodedData) {
         return WindowOrWorkerGlobalScopeMixin.atob(encodedData, this);
     }
 
+    /**
+     * The JavaScript function {@code fetch()}.
+     * @param input a string or a Request
+     * @param init optional init dictionary
+     * @return a promise resolving to the response
+     */
+    @JsxFunction
+    public NativePromise fetch(final Object input, final Object init) {
+        try {
+            final VarScope scope = JavaScriptEngine.getTopCallScope();
+            final Request request =
+                    (Request) JavaScriptEngine.newObject(scope, "Request", new Object[] {input, init});
+            final WebRequest webRequest = request.toWebRequest(this);
+            final WebResponse webResponse = getWebWindow().getWebClient().loadWebResponse(webRequest);
+
+            final Response response = (Response) JavaScriptEngine.newObject(scope,
+                    "Response", new Object[] {JavaScriptEngine.UNDEFINED, JavaScriptEngine.UNDEFINED});
+            response.setFromWebResponse(webResponse, webRequest.getUrl().toExternalForm());
+            return setupPromise(() -> response);
+        }
+        catch (final Exception e) {
+            return setupRejectedPromise(() -> {
+                final VarScope scope = JavaScriptEngine.getTopCallScope();
+                final Object typeError = ScriptableObject.getProperty(scope, "TypeError");
+                if (typeError instanceof Function function) {
+                    final String message = org.htmlunit.util.StringUtils.isEmptyOrNull(e.getMessage())
+                            ? "Failed to fetch" : e.getMessage();
+                    return function.construct(Context.getCurrentContext(), scope, new Object[] {message});
+                }
+                return e.getMessage();
+            });
+        }
+    }
+
     /**
      * The JavaScript function {@code confirm}.
      * @param message the message
diff --git a/src/main/java/org/htmlunit/javascript/host/fetch/FetchBodyMixin.java b/src/main/java/org/htmlunit/javascript/host/fetch/FetchBodyMixin.java
new file mode 100644
index 0000000000..0764dcb1ed
--- /dev/null
+++ b/src/main/java/org/htmlunit/javascript/host/fetch/FetchBodyMixin.java
@@ -0,0 +1,210 @@
+/*
+ * Copyright (c) 2002-2026 Gargoyle Software Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.htmlunit.javascript.host.fetch;
+
+import static java.nio.charset.StandardCharsets.UTF_8;
+
+import java.io.IOException;
+
+import org.htmlunit.corejs.javascript.Context;
+import org.htmlunit.corejs.javascript.Function;
+import org.htmlunit.corejs.javascript.NativeArrayBuffer;
+import org.htmlunit.corejs.javascript.NativePromise;
+import org.htmlunit.corejs.javascript.ScriptableObject;
+import org.htmlunit.corejs.javascript.VarScope;
+import org.htmlunit.corejs.javascript.json.JsonParser;
+import org.htmlunit.corejs.javascript.json.JsonParser.ParseException;
+import org.htmlunit.javascript.HtmlUnitScriptable;
+import org.htmlunit.javascript.JavaScriptEngine;
+import org.htmlunit.javascript.configuration.JsxFunction;
+import org.htmlunit.javascript.configuration.JsxGetter;
+import org.htmlunit.javascript.host.file.Blob;
+import org.htmlunit.javascript.host.xml.FormData;
+
+/**
+ * Shared body handling for fetch Request/Response objects.
+ *
+ * @author Ronald Brill
+ */
+public class FetchBodyMixin extends HtmlUnitScriptable {
+
+    private byte[] bodyBytes_ = new byte[0];
+    private String contentType_;
+    private boolean bodyUsed_;
+
+    @JsxGetter
+    public Object getBody() {
+        return null;
+    }
+
+    @JsxGetter
+    public boolean isBodyUsed() {
+        return bodyUsed_;
+    }
+
+    @JsxFunction
+    public NativePromise text() {
+        if (bodyUsed_) {
+            return rejectedTypeErrorPromise("Body has already been consumed.");
+        }
+        bodyUsed_ = true;
+        return setupPromise(() -> new String(bodyBytes_, UTF_8));
+    }
+
+    @JsxFunction
+    public NativePromise json() {
+        if (bodyUsed_) {
+            return rejectedTypeErrorPromise("Body has already been consumed.");
+        }
+        bodyUsed_ = true;
+        try {
+            final String json = new String(bodyBytes_, UTF_8);
+            final Object parsed = new JsonParser(Context.getCurrentContext(), getParentScope()).parseValue(json);
+            return setupPromise(() -> parsed);
+        }
+        catch (final ParseException e) {
+            return rejectedTypeErrorPromise(e.getMessage());
+        }
+    }
+
+    @JsxFunction
+    public NativePromise arrayBuffer() {
+        if (bodyUsed_) {
+            return rejectedTypeErrorPromise("Body has already been consumed.");
+        }
+        bodyUsed_ = true;
+        return setupPromise(() -> {
+            final NativeArrayBuffer buffer = new NativeArrayBuffer(bodyBytes_.length);
+            System.arraycopy(bodyBytes_, 0, buffer.getBuffer(), 0, bodyBytes_.length);
+            buffer.setParentScope(getParentScope());
+            buffer.setPrototype(ScriptableObject.getClassPrototype(getParentScope(), buffer.getClassName()));
+            return buffer;
+        });
+    }
+
+    @JsxFunction
+    public NativePromise blob() {
+        if (bodyUsed_) {
+            return rejectedTypeErrorPromise("Body has already been consumed.");
+        }
+        bodyUsed_ = true;
+        return setupPromise(() -> {
+            final Blob blob = new Blob(bodyBytes_, contentType_);
+            blob.setParentScope(getParentScope());
+            blob.setPrototype(getPrototype(Blob.class));
+            return blob;
+        });
+    }
+
+    @JsxFunction
+    public NativePromise formData() {
+        if (bodyUsed_) {
+            return rejectedTypeErrorPromise("Body has already been consumed.");
+        }
+        bodyUsed_ = true;
+        return setupPromise(this::buildFormData);
+    }
+
+    protected byte[] getBodyBytes() {
+        return bodyBytes_;
+    }
+
+    protected String getBodyContentType() {
+        return contentType_;
+    }
+
+    protected void setBody(final byte[] bodyBytes, final String contentType) {
+        bodyBytes_ = bodyBytes != null ? bodyBytes.clone() : new byte[0];
+        contentType_ = contentType;
+        bodyUsed_ = false;
+    }
+
+    protected void copyBodyTo(final FetchBodyMixin other) {
+        other.bodyBytes_ = bodyBytes_.clone();
+        other.contentType_ = contentType_;
+        other.bodyUsed_ = false;
+    }
+
+    protected Object createTypeErrorObject(final String message) {
+        final VarScope scope = ScriptableObject.getTopLevelScope(getParentScope());
+        final Object typeError = ScriptableObject.getProperty(scope, "TypeError");
+        if (typeError instanceof Function function) {
+            return function.construct(Context.getCurrentContext(), scope, new Object[] {message});
+        }
+        return message;
+    }
+
+    protected NativePromise rejectedTypeErrorPromise(final String message) {
+        return setupRejectedPromise(() -> createTypeErrorObject(message));
+    }
+
+    private FormData buildFormData() throws IOException {
+        final FormData formData = new FormData();
+        formData.setParentScope(getParentScope());
+        formData.setPrototype(getPrototype(FormData.class));
+        formData.jsConstructor(JavaScriptEngine.UNDEFINED);
+
+        final String contentType = contentType_ != null ? contentType_.toLowerCase() : "";
+        if (contentType.startsWith("multipart/form-data;")) {
+            final String marker = "boundary=";
+            final int boundaryStart = contentType.indexOf(marker);
+            if (boundaryStart > -1) {
+                final String boundary = contentType.substring(boundaryStart + marker.length()).trim();
+                final String body = new String(bodyBytes_, UTF_8);
+                final String[] parts = body.split("--" + boundary);
+                for (final String part : parts) {
+                    final int headerEnd = part.indexOf("\r\n\r\n");
+                    if (headerEnd < 0) {
+                        continue;
+                    }
+                    final String headers = part.substring(0, headerEnd);
+                    final String data = part.substring(headerEnd + 4).replaceFirst("\r\n$", "");
+                    final String name = extractName(headers);
+                    if (name != null) {
+                        formData.append(name, data, JavaScriptEngine.UNDEFINED);
+                    }
+                }
+                return formData;
+            }
+        }
+
+        final String body = new String(bodyBytes_, UTF_8);
+        if (!body.isEmpty()) {
+            final String[] pairs = body.split("&");
+            for (final String pair : pairs) {
+                final int equals = pair.indexOf('=');
+                final String name = equals < 0 ? pair : pair.substring(0, equals);
+                final String value = equals < 0 ? "" : pair.substring(equals + 1);
+                formData.append(org.htmlunit.util.UrlUtils.decode(name),
+                        org.htmlunit.util.UrlUtils.decode(value), JavaScriptEngine.UNDEFINED);
+            }
+        }
+
+        return formData;
+    }
+
+    private static String extractName(final String headers) {
+        final String marker = "name=\"";
+        final int start = headers.indexOf(marker);
+        if (start < 0) {
+            return null;
+        }
+        final int end = headers.indexOf('"', start + marker.length());
+        if (end < 0) {
+            return null;
+        }
+        return headers.substring(start + marker.length(), end);
+    }
+}
diff --git a/src/main/java/org/htmlunit/javascript/host/fetch/Headers.java b/src/main/java/org/htmlunit/javascript/host/fetch/Headers.java
index f9600e183e..d930847b63 100644
--- a/src/main/java/org/htmlunit/javascript/host/fetch/Headers.java
+++ b/src/main/java/org/htmlunit/javascript/host/fetch/Headers.java
@@ -14,9 +14,31 @@
  */
 package org.htmlunit.javascript.host.fetch;
 
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Locale;
+import java.util.Map;
+
+import org.htmlunit.corejs.javascript.Context;
+import org.htmlunit.corejs.javascript.ES6Iterator;
+import org.htmlunit.corejs.javascript.Function;
+import org.htmlunit.corejs.javascript.IteratorLikeIterable;
+import org.htmlunit.corejs.javascript.NativeObject;
+import org.htmlunit.corejs.javascript.ScriptRuntime;
+import org.htmlunit.corejs.javascript.Scriptable;
+import org.htmlunit.corejs.javascript.SymbolKey;
+import org.htmlunit.corejs.javascript.TopLevel;
+import org.htmlunit.corejs.javascript.VarScope;
 import org.htmlunit.javascript.HtmlUnitScriptable;
+import org.htmlunit.javascript.JavaScriptEngine;
 import org.htmlunit.javascript.configuration.JsxClass;
 import org.htmlunit.javascript.configuration.JsxConstructor;
+import org.htmlunit.javascript.configuration.JsxFunction;
+import org.htmlunit.javascript.configuration.JsxSymbol;
+import org.htmlunit.util.NameValuePair;
 
 /**
  * A JavaScript object for {@code Headers}.
@@ -27,11 +49,298 @@
 @JsxClass
 public class Headers extends HtmlUnitScriptable {
 
+    /** Constant used to register the prototype in the context. */
+    public static final String HEADERS_TAG = "Headers";
+
+    private final List<NameValuePair> headers_ = new ArrayList<>();
+
+    /**
+     * {@link ES6Iterator} implementation for js support.
+     */
+    public static final class NativeHeadersIterator extends ES6Iterator {
+        enum Type { KEYS, VALUES, BOTH }
+
+        private final Type type_;
+        private final String className_;
+        private final transient Iterator<NameValuePair> iterator_;
+
+        /**
+         * Init.
+         * @param scope the scope
+         * @param className the class name
+         */
+        public static void init(final TopLevel scope, final String className) {
+            ES6Iterator.init(scope, false, new NativeHeadersIterator(className), HEADERS_TAG);
+        }
+
+        /**
+         * Ctor.
+         * @param className the class name
+         */
+        public NativeHeadersIterator(final String className) {
+            super();
+            iterator_ = Collections.emptyIterator();
+            type_ = Type.BOTH;
+            className_ = className;
+        }
+
+        /**
+         * Ctor.
+         * @param scope the scope
+         * @param className the class name
+         * @param type the type
+         * @param iterator the backing iterator
+         */
+        public NativeHeadersIterator(final VarScope scope, final String className, final Type type,
+                final Iterator<NameValuePair> iterator) {
+            super(scope, HEADERS_TAG);
+            iterator_ = iterator;
+            type_ = type;
+            className_ = className;
+        }
+
+        @Override
+        public String getClassName() {
+            return className_;
+        }
+
+        @Override
+        protected boolean isDone(final Context cx, final VarScope scope) {
+            return !iterator_.hasNext();
+        }
+
+        @Override
+        protected Object nextValue(final Context cx, final VarScope scope) {
+            final NameValuePair e = iterator_.next();
+            return switch (type_) {
+                case KEYS -> e.getName();
+                case VALUES -> e.getValue();
+                case BOTH -> cx.newArray(scope, new Object[] {e.getName(), e.getValue()});
+            };
+        }
+    }
+
     /**
      * JavaScript constructor.
      */
     @JsxConstructor
-    public void jsConstructor() {
-        // nothing to do
+    public void jsConstructor(final Object init) {
+        if (init == null || JavaScriptEngine.isUndefined(init)) {
+            return;
+        }
+
+        if (init instanceof Headers headers) {
+            headers_.addAll(headers.headers_);
+            return;
+        }
+
+        if (init instanceof NativeObject object) {
+            for (final Map.Entry<Object, Object> entry : object.entrySet()) {
+                append(JavaScriptEngine.toString(entry.getKey()), JavaScriptEngine.toString(entry.getValue()));
+            }
+            return;
+        }
+
+        if (init instanceof Scriptable scriptable && hasProperty(scriptable, SymbolKey.ITERATOR)) {
+            final Context cx = Context.getCurrentContext();
+            try (IteratorLikeIterable itr = buildIteratorLikeIterable(cx, scriptable)) {
+                for (final Object nameValue : itr) {
+                    if (!(nameValue instanceof Scriptable pair)) {
+                        throw JavaScriptEngine.typeError("The provided value cannot be converted to a sequence.");
+                    }
+                    if (!hasProperty(pair, SymbolKey.ITERATOR)) {
+                        throw JavaScriptEngine.typeError("The object must have a callable @@iterator property.");
+                    }
+
+                    try (IteratorLikeIterable pairItr = buildIteratorLikeIterable(cx, pair)) {
+                        final Iterator<Object> iterator = pairItr.iterator();
+                        final Object name = iterator.hasNext() ? iterator.next() : NOT_FOUND;
+                        final Object value = iterator.hasNext() ? iterator.next() : NOT_FOUND;
+                        if (name == NOT_FOUND || value == NOT_FOUND || iterator.hasNext()) {
+                            throw JavaScriptEngine.typeError("Sequence initializer must only contain pair elements.");
+                        }
+                        append(JavaScriptEngine.toString(name), JavaScriptEngine.toString(value));
+                    }
+                }
+            }
+            return;
+        }
+
+        throw JavaScriptEngine.typeError("Failed to construct 'Headers': Invalid initializer");
+    }
+
+    /**
+     * Appends a header to this Headers object.
+     * @param name the header name
+     * @param value the header value
+     */
+    @JsxFunction
+    public void append(final String name, final String value) {
+        headers_.add(new NameValuePair(normalizeName(name), JavaScriptEngine.toString(value)));
+    }
+
+    /**
+     * Deletes all matching header values.
+     * @param name the header name
+     */
+    @JsxFunction(functionName = "delete")
+    @Override
+    public void delete(final String name) {
+        final String normalizedName = normalizeName(name);
+        headers_.removeIf(entry -> normalizedName.equals(entry.getName()));
+    }
+
+    /**
+     * Returns the first value for the header name.
+     * @param name the header name
+     * @return the value or null
+     */
+    @JsxFunction
+    public String get(final String name) {
+        final String normalizedName = normalizeName(name);
+        String result = null;
+        for (final NameValuePair entry : headers_) {
+            if (normalizedName.equals(entry.getName())) {
+                if (result == null) {
+                    result = entry.getValue();
+                }
+                else {
+                    result += ", " + entry.getValue();
+                }
+            }
+        }
+        return result;
+    }
+
+    /**
+     * Returns all set-cookie header values.
+     * @return the set-cookie values
+     */
+    @JsxFunction
+    public Scriptable getSetCookie() {
+        final List<String> result = new ArrayList<>();
+        for (final NameValuePair entry : headers_) {
+            if ("set-cookie".equals(entry.getName())) {
+                result.add(entry.getValue());
+            }
+        }
+        return JavaScriptEngine.newArray(getParentScope(), result.toArray());
+    }
+
+    /**
+     * Returns if this Headers contains the given name.
+     * @param name the header name
+     * @return true if this Headers contains the given name
+     */
+    @JsxFunction
+    public boolean has(final String name) {
+        final String normalizedName = normalizeName(name);
+        for (final NameValuePair entry : headers_) {
+            if (normalizedName.equals(entry.getName())) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Sets a header value.
+     * @param name the header name
+     * @param value the value
+     */
+    @JsxFunction
+    public void set(final String name, final String value) {
+        final String normalizedName = normalizeName(name);
+        delete(normalizedName);
+        headers_.add(new NameValuePair(normalizedName, JavaScriptEngine.toString(value)));
+    }
+
+    /**
+     * Allows iteration through all key/value pairs.
+     * @param callback function to execute on each key/value pair
+     */
+    @JsxFunction
+    public void forEach(final Object callback) {
+        if (!(callback instanceof Function fun)) {
+            throw JavaScriptEngine.typeError(
+                    "Foreach callback '" + JavaScriptEngine.toString(callback) + "' is not a function");
+        }
+
+        final List<NameValuePair> entries = entriesList();
+        for (final NameValuePair entry : entries) {
+            fun.call(Context.getCurrentContext(), getParentScope(), this,
+                    new Object[] {entry.getValue(), entry.getName(), this});
+        }
+    }
+
+    /**
+     * Returns an iterator of key/value pairs.
+     * @return the iterator
+     */
+    @JsxFunction
+    @JsxSymbol(symbolName = "iterator")
+    public ES6Iterator entries() {
+        return new NativeHeadersIterator(getParentScope(),
+                "Headers Iterator", NativeHeadersIterator.Type.BOTH, entriesList().iterator());
+    }
+
+    /**
+     * Returns an iterator of header keys.
+     * @return the iterator
+     */
+    @JsxFunction
+    public ES6Iterator keys() {
+        return new NativeHeadersIterator(getParentScope(),
+                "Headers Iterator", NativeHeadersIterator.Type.KEYS, entriesList().iterator());
+    }
+
+    /**
+     * Returns an iterator of header values.
+     * @return the iterator
+     */
+    @JsxFunction
+    public ES6Iterator values() {
+        return new NativeHeadersIterator(getParentScope(),
+                "Headers Iterator", NativeHeadersIterator.Type.VALUES, entriesList().iterator());
+    }
+
+    /**
+     * @return all request header entries for this object
+     */
+    List<NameValuePair> entriesList() {
+        final Map<String, String> merged = new LinkedHashMap<>();
+        for (final NameValuePair entry : headers_) {
+            final String previous = merged.get(entry.getName());
+            if (previous == null) {
+                merged.put(entry.getName(), entry.getValue());
+            }
+            else {
+                merged.put(entry.getName(), previous + ", " + entry.getValue());
+            }
+        }
+
+        final List<NameValuePair> result = new ArrayList<>(merged.size());
+        for (final Map.Entry<String, String> entry : merged.entrySet()) {
+            result.add(new NameValuePair(entry.getKey(), entry.getValue()));
+        }
+        return result;
+    }
+
+    void copyFrom(final Headers headers) {
+        headers_.clear();
+        headers_.addAll(headers.headers_);
+    }
+
+    void appendRaw(final String name, final String value) {
+        headers_.add(new NameValuePair(normalizeName(name), value));
+    }
+
+    private static IteratorLikeIterable buildIteratorLikeIterable(final Context cx, final Scriptable iterable) {
+        final Object iterator = ScriptRuntime.callIterator(iterable, cx, iterable.getParentScope());
+        return new IteratorLikeIterable(cx, iterable.getParentScope(), iterator);
+    }
+
+    private static String normalizeName(final String name) {
+        return JavaScriptEngine.toString(name).toLowerCase(Locale.ROOT);
     }
 }
diff --git a/src/main/java/org/htmlunit/javascript/host/fetch/Request.java b/src/main/java/org/htmlunit/javascript/host/fetch/Request.java
index 5ce97f3865..66776c95a3 100644
--- a/src/main/java/org/htmlunit/javascript/host/fetch/Request.java
+++ b/src/main/java/org/htmlunit/javascript/host/fetch/Request.java
@@ -14,9 +14,31 @@
  */
 package org.htmlunit.javascript.host.fetch;
 
-import org.htmlunit.javascript.HtmlUnitScriptable;
+import static java.nio.charset.StandardCharsets.UTF_8;
+
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.util.Locale;
+
+import org.htmlunit.FormEncodingType;
+import org.htmlunit.HttpHeader;
+import org.htmlunit.HttpMethod;
+import org.htmlunit.Page;
+import org.htmlunit.WebRequest;
+import org.htmlunit.corejs.javascript.NativeArrayBufferView;
+import org.htmlunit.corejs.javascript.Scriptable;
+import org.htmlunit.corejs.javascript.ScriptableObject;
+import org.htmlunit.javascript.JavaScriptEngine;
 import org.htmlunit.javascript.configuration.JsxClass;
 import org.htmlunit.javascript.configuration.JsxConstructor;
+import org.htmlunit.javascript.configuration.JsxFunction;
+import org.htmlunit.javascript.configuration.JsxGetter;
+import org.htmlunit.javascript.host.URLSearchParams;
+import org.htmlunit.javascript.host.Window;
+import org.htmlunit.javascript.host.file.Blob;
+import org.htmlunit.javascript.host.html.HTMLDocument;
+import org.htmlunit.javascript.host.xml.FormData;
+import org.htmlunit.javascript.host.xml.XMLDocument;
 
 /**
  * A JavaScript object for {@code Request}.
@@ -25,13 +47,298 @@
  * @author Ronald Brill
  */
 @JsxClass
-public class Request extends HtmlUnitScriptable {
+public class Request extends FetchBodyMixin {
+
+    private String url_;
+    private String method_ = HttpMethod.GET.name();
+    private Headers headers_;
+    private String mode_ = "cors";
+    private String credentials_ = "same-origin";
+    private String cache_ = "default";
+    private String redirect_ = "follow";
+    private String referrer_ = "about:client";
+    private String referrerPolicy_ = "";
+    private String integrity_ = "";
+    private boolean keepalive_;
+    private Object signal_;
+    private Object body_;
 
     /**
      * JavaScript constructor.
      */
     @JsxConstructor
-    public void jsConstructor() {
-        // nothing to do
+    public void jsConstructor(final Object input, final Object init) {
+        headers_ = newHeaders();
+        signal_ = JavaScriptEngine.UNDEFINED;
+
+        if (input instanceof Request request) {
+            copyFrom(request);
+        }
+        else {
+            final String inputString = JavaScriptEngine.toString(input);
+            url_ = resolveUrl(inputString);
+        }
+
+        if (init instanceof Scriptable scriptable) {
+            applyInit(scriptable);
+        }
+    }
+
+    @JsxGetter
+    public String getUrl() {
+        return url_;
+    }
+
+    @JsxGetter
+    public String getMethod() {
+        return method_;
+    }
+
+    @JsxGetter
+    public Headers getHeaders() {
+        return headers_;
+    }
+
+    @JsxGetter
+    public String getMode() {
+        return mode_;
+    }
+
+    @JsxGetter
+    public String getCredentials() {
+        return credentials_;
+    }
+
+    @JsxGetter
+    public String getCache() {
+        return cache_;
+    }
+
+    @JsxGetter
+    public String getRedirect() {
+        return redirect_;
+    }
+
+    @JsxGetter
+    public String getReferrer() {
+        return referrer_;
+    }
+
+    @JsxGetter
+    public String getReferrerPolicy() {
+        return referrerPolicy_;
+    }
+
+    @JsxGetter
+    public String getIntegrity() {
+        return integrity_;
+    }
+
+    @JsxGetter
+    public boolean isKeepalive() {
+        return keepalive_;
+    }
+
+    @JsxGetter
+    public Object getSignal() {
+        return signal_;
+    }
+
+    @Override
+    @JsxGetter
+    public Object getBody() {
+        return body_;
+    }
+
+    @JsxFunction
+    public Request clone() {
+        final Request clone = new Request();
+        clone.setParentScope(getParentScope());
+        clone.setPrototype(getPrototype(Request.class));
+        clone.copyFrom(this);
+        return clone;
+    }
+
+    public WebRequest toWebRequest(final Window window) throws MalformedURLException {
+        final URL requestUrl = new URL(url_);
+        final String protocol = requestUrl.getProtocol();
+        if (!"http".equals(protocol) && !"https".equals(protocol)
+                && !"data".equals(protocol) && !"blob".equals(protocol)) {
+            throw JavaScriptEngine.typeError("Failed to fetch");
+        }
+
+        final WebRequest webRequest = new WebRequest(requestUrl,
+                getBrowserVersion().getXmlHttpRequestAcceptHeader(),
+                getBrowserVersion().getAcceptEncodingHeader());
+        webRequest.setCharset(UTF_8);
+        webRequest.setDefaultResponseContentCharset(UTF_8);
+
+        final Page page = window.getWebWindow().getEnclosedPage();
+        if (page != null) {
+            webRequest.setRefererHeader(page.getUrl());
+        }
+
+        webRequest.setHttpMethod(HttpMethod.valueOf(method_));
+        for (final org.htmlunit.util.NameValuePair entry : headers_.entriesList()) {
+            webRequest.setAdditionalHeader(entry.getName(), entry.getValue());
+        }
+
+        applyBodyToWebRequest(webRequest);
+        return webRequest;
+    }
+
+    private void copyFrom(final Request request) {
+        url_ = request.url_;
+        method_ = request.method_;
+        headers_ = newHeaders();
+        headers_.copyFrom(request.headers_);
+        mode_ = request.mode_;
+        credentials_ = request.credentials_;
+        cache_ = request.cache_;
+        redirect_ = request.redirect_;
+        referrer_ = request.referrer_;
+        referrerPolicy_ = request.referrerPolicy_;
+        integrity_ = request.integrity_;
+        keepalive_ = request.keepalive_;
+        signal_ = request.signal_;
+        body_ = request.body_;
+        request.copyBodyTo(this);
+    }
+
+    private Headers newHeaders() {
+        final Headers headers = new Headers();
+        headers.setParentScope(getParentScope());
+        headers.setPrototype(getPrototype(Headers.class));
+        headers.jsConstructor(JavaScriptEngine.UNDEFINED);
+        return headers;
+    }
+
+    private void applyInit(final Scriptable init) {
+        final Object method = ScriptableObject.getProperty(init, "method");
+        if (!JavaScriptEngine.isUndefined(method)) {
+            final String methodString = JavaScriptEngine.toString(method).toUpperCase(Locale.ROOT);
+            HttpMethod.validateHttpMethodName(methodString);
+            method_ = methodString;
+        }
+
+        final Object headers = ScriptableObject.getProperty(init, "headers");
+        if (!JavaScriptEngine.isUndefined(headers)) {
+            headers_ = newHeaders();
+            headers_.jsConstructor(headers);
+        }
+
+        final Object body = ScriptableObject.getProperty(init, "body");
+        if (!JavaScriptEngine.isUndefined(body) && body != null) {
+            if (HttpMethod.GET.name().equals(method_) || HttpMethod.HEAD.name().equals(method_)) {
+                throw JavaScriptEngine.typeError("Request with GET/HEAD method cannot have body.");
+            }
+            body_ = body;
+            if (body instanceof Blob blob) {
+                setBody(blob.getBytes(), blob.getType());
+            }
+            else if (body instanceof URLSearchParams params) {
+                setBody(params.jsToString().getBytes(UTF_8), "application/x-www-form-urlencoded");
+            }
+            else if (body instanceof NativeArrayBufferView view) {
+                setBody(view.getBuffer().getBuffer(), null);
+            }
+            else {
+                setBody(JavaScriptEngine.toString(body).getBytes(UTF_8), null);
+            }
+        }
+
+        final Object mode = ScriptableObject.getProperty(init, "mode");
+        if (!JavaScriptEngine.isUndefined(mode)) {
+            mode_ = JavaScriptEngine.toString(mode);
+        }
+        final Object credentials = ScriptableObject.getProperty(init, "credentials");
+        if (!JavaScriptEngine.isUndefined(credentials)) {
+            credentials_ = JavaScriptEngine.toString(credentials);
+        }
+        final Object cache = ScriptableObject.getProperty(init, "cache");
+        if (!JavaScriptEngine.isUndefined(cache)) {
+            cache_ = JavaScriptEngine.toString(cache);
+        }
+        final Object redirect = ScriptableObject.getProperty(init, "redirect");
+        if (!JavaScriptEngine.isUndefined(redirect)) {
+            redirect_ = JavaScriptEngine.toString(redirect);
+        }
+        final Object referrer = ScriptableObject.getProperty(init, "referrer");
+        if (!JavaScriptEngine.isUndefined(referrer)) {
+            referrer_ = JavaScriptEngine.toString(referrer);
+        }
+        final Object referrerPolicy = ScriptableObject.getProperty(init, "referrerPolicy");
+        if (!JavaScriptEngine.isUndefined(referrerPolicy)) {
+            referrerPolicy_ = JavaScriptEngine.toString(referrerPolicy);
+        }
+        final Object integrity = ScriptableObject.getProperty(init, "integrity");
+        if (!JavaScriptEngine.isUndefined(integrity)) {
+            integrity_ = JavaScriptEngine.toString(integrity);
+        }
+        final Object keepalive = ScriptableObject.getProperty(init, "keepalive");
+        if (!JavaScriptEngine.isUndefined(keepalive)) {
+            keepalive_ = JavaScriptEngine.toBoolean(keepalive);
+        }
+        final Object signal = ScriptableObject.getProperty(init, "signal");
+        if (!JavaScriptEngine.isUndefined(signal)) {
+            signal_ = signal;
+        }
+    }
+
+    private String resolveUrl(final String urlString) {
+        try {
+            final Page page = getWindow().getWebWindow().getEnclosedPage();
+            if (page instanceof org.htmlunit.html.HtmlPage htmlPage) {
+                return htmlPage.getFullyQualifiedUrl(urlString).toExternalForm();
+            }
+            return new URL(urlString).toExternalForm();
+        }
+        catch (final MalformedURLException e) {
+            throw JavaScriptEngine.typeError("Failed to construct 'Request': Invalid URL");
+        }
+    }
+
+    private void applyBodyToWebRequest(final WebRequest webRequest) {
+        if (body_ == null || JavaScriptEngine.isUndefined(body_)) {
+            return;
+        }
+
+        if (body_ instanceof FormData formData) {
+            formData.fillRequest(webRequest);
+            return;
+        }
+        if (body_ instanceof URLSearchParams params) {
+            params.fillRequest(webRequest);
+            webRequest.addHint(WebRequest.HttpHint.IncludeCharsetInContentTypeHeader);
+            return;
+        }
+        if (body_ instanceof Blob blob) {
+            blob.fillRequest(webRequest);
+            return;
+        }
+        if (body_ instanceof NativeArrayBufferView view) {
+            webRequest.setRequestBody(new String(view.getBuffer().getBuffer(), UTF_8));
+            webRequest.setEncodingType(null);
+            return;
+        }
+        if (body_ instanceof HTMLDocument || body_ instanceof XMLDocument) {
+            final String body = JavaScriptEngine.toString(body_);
+            webRequest.setRequestBody(body);
+            webRequest.setCharset(UTF_8);
+            if (webRequest.getAdditionalHeader(HttpHeader.CONTENT_TYPE) == null) {
+                webRequest.setAdditionalHeader(HttpHeader.CONTENT_TYPE, "text/plain;charset=UTF-8");
+                webRequest.setEncodingType(FormEncodingType.TEXT_PLAIN);
+            }
+            return;
+        }
+
+        final String body = JavaScriptEngine.toString(body_);
+        if (!body.isEmpty()) {
+            webRequest.setRequestBody(body);
+            webRequest.setCharset(UTF_8);
+            if (webRequest.getAdditionalHeader(HttpHeader.CONTENT_TYPE) == null) {
+                webRequest.setEncodingType(FormEncodingType.TEXT_PLAIN);
+            }
+        }
     }
 }
diff --git a/src/main/java/org/htmlunit/javascript/host/fetch/Response.java b/src/main/java/org/htmlunit/javascript/host/fetch/Response.java
index 7b55b54ec0..fc23935360 100644
--- a/src/main/java/org/htmlunit/javascript/host/fetch/Response.java
+++ b/src/main/java/org/htmlunit/javascript/host/fetch/Response.java
@@ -14,9 +14,20 @@
  */
 package org.htmlunit.javascript.host.fetch;
 
-import org.htmlunit.javascript.HtmlUnitScriptable;
+import static java.nio.charset.StandardCharsets.UTF_8;
+
+import java.util.List;
+
+import org.htmlunit.WebResponse;
+import org.htmlunit.corejs.javascript.ScriptableObject;
+import org.htmlunit.corejs.javascript.VarScope;
+import org.htmlunit.javascript.JavaScriptEngine;
 import org.htmlunit.javascript.configuration.JsxClass;
 import org.htmlunit.javascript.configuration.JsxConstructor;
+import org.htmlunit.javascript.configuration.JsxFunction;
+import org.htmlunit.javascript.configuration.JsxGetter;
+import org.htmlunit.javascript.configuration.JsxStaticFunction;
+import org.htmlunit.util.NameValuePair;
 
 /**
  * A JavaScript object for {@code Response}.
@@ -25,13 +36,157 @@
  * @author Ronald Brill
  */
 @JsxClass
-public class Response extends HtmlUnitScriptable {
+public class Response extends FetchBodyMixin {
+
+    private int status_ = 200;
+    private String statusText_ = "";
+    private Headers headers_;
+    private String url_ = "";
+    private boolean redirected_;
+    private String type_ = "default";
 
     /**
      * JavaScript constructor.
      */
     @JsxConstructor
-    public void jsConstructor() {
-        // nothing to do
+    public void jsConstructor(final Object body, final Object init) {
+        headers_ = newHeaders();
+        if (init instanceof org.htmlunit.corejs.javascript.Scriptable scriptable) {
+            final Object status = ScriptableObject.getProperty(scriptable, "status");
+            if (!JavaScriptEngine.isUndefined(status)) {
+                status_ = JavaScriptEngine.toInt32(status);
+            }
+
+            final Object statusText = ScriptableObject.getProperty(scriptable, "statusText");
+            if (!JavaScriptEngine.isUndefined(statusText)) {
+                statusText_ = JavaScriptEngine.toString(statusText);
+            }
+
+            final Object headers = ScriptableObject.getProperty(scriptable, "headers");
+            if (!JavaScriptEngine.isUndefined(headers)) {
+                headers_ = newHeaders();
+                headers_.jsConstructor(headers);
+            }
+        }
+        setBodyFrom(body);
+    }
+
+    @JsxStaticFunction
+    public static Response ok() {
+        final VarScope scope = JavaScriptEngine.getTopCallScope();
+        return (Response) JavaScriptEngine.newObject(scope, "Response", new Object[] {JavaScriptEngine.UNDEFINED,
+                JavaScriptEngine.UNDEFINED});
+    }
+
+    @JsxStaticFunction
+    public static Response error() {
+        final Response response = ok();
+        response.status_ = 0;
+        response.statusText_ = "";
+        response.type_ = "error";
+        return response;
+    }
+
+    @JsxStaticFunction
+    public static Response redirect(final String url, final Object status) {
+        final Response response = ok();
+        final int redirectStatus = JavaScriptEngine.isUndefined(status) ? 302 : JavaScriptEngine.toInt32(status);
+        response.status_ = redirectStatus;
+        response.headers_.set("location", JavaScriptEngine.toString(url));
+        return response;
+    }
+
+    @JsxGetter
+    public boolean isOk() {
+        return status_ >= 200 && status_ < 300;
+    }
+
+    @JsxGetter
+    public int getStatus() {
+        return status_;
+    }
+
+    @JsxGetter
+    public String getStatusText() {
+        return statusText_;
+    }
+
+    @JsxGetter
+    public Headers getHeaders() {
+        return headers_;
+    }
+
+    @JsxGetter
+    public String getUrl() {
+        return url_;
+    }
+
+    @JsxGetter
+    public boolean isRedirected() {
+        return redirected_;
+    }
+
+    @JsxGetter
+    public String getType() {
+        return type_;
+    }
+
+    @JsxFunction
+    public Response clone() {
+        final Response clone = new Response();
+        clone.setParentScope(getParentScope());
+        clone.setPrototype(getPrototype(Response.class));
+        clone.status_ = status_;
+        clone.statusText_ = statusText_;
+        clone.headers_ = clone.newHeaders();
+        clone.headers_.copyFrom(headers_);
+        clone.url_ = url_;
+        clone.redirected_ = redirected_;
+        clone.type_ = type_;
+        copyBodyTo(clone);
+        return clone;
+    }
+
+    public void setFromWebResponse(final WebResponse webResponse, final String requestUrl) {
+        status_ = webResponse.getStatusCode();
+        statusText_ = webResponse.getStatusMessage();
+        headers_ = newHeaders();
+        final List<NameValuePair> responseHeaders = webResponse.getResponseHeaders();
+        for (final NameValuePair header : responseHeaders) {
+            headers_.appendRaw(header.getName(), header.getValue());
+        }
+
+        url_ = webResponse.getWebRequest().getUrl().toExternalForm();
+        redirected_ = !requestUrl.equals(url_);
+        type_ = "basic";
+        setBody(webResponse.getContentAsBytes(), webResponse.getContentType());
+    }
+
+    private Headers newHeaders() {
+        final Headers headers = new Headers();
+        headers.setParentScope(getParentScope());
+        headers.setPrototype(getPrototype(Headers.class));
+        headers.jsConstructor(JavaScriptEngine.UNDEFINED);
+        return headers;
+    }
+
+    private void setBodyFrom(final Object body) {
+        if (body == null || JavaScriptEngine.isUndefined(body)) {
+            setBody(new byte[0], null);
+            return;
+        }
+        if (body instanceof org.htmlunit.javascript.host.file.Blob blob) {
+            setBody(blob.getBytes(), blob.getType());
+            return;
+        }
+        if (body instanceof org.htmlunit.corejs.javascript.NativeArrayBufferView view) {
+            setBody(view.getBuffer().getBuffer(), null);
+            return;
+        }
+        if (body instanceof org.htmlunit.javascript.host.URLSearchParams params) {
+            setBody(params.jsToString().getBytes(UTF_8), "application/x-www-form-urlencoded");
+            return;
+        }
+        setBody(JavaScriptEngine.toString(body).getBytes(UTF_8), null);
     }
 }
diff --git a/src/test/java/org/htmlunit/javascript/host/fetch/FetchTest.java b/src/test/java/org/htmlunit/javascript/host/fetch/FetchTest.java
index 23d1a3b10d..b1244aea37 100644
--- a/src/test/java/org/htmlunit/javascript/host/fetch/FetchTest.java
+++ b/src/test/java/org/htmlunit/javascript/host/fetch/FetchTest.java
@@ -14,22 +14,14 @@
  */
 package org.htmlunit.javascript.host.fetch;
 
-import java.util.ArrayList;
-import java.util.List;
-
-import org.htmlunit.HttpHeader;
 import org.htmlunit.WebDriverTestCase;
-import org.htmlunit.WebRequest;
 import org.htmlunit.junit.annotation.Alerts;
-import org.htmlunit.junit.annotation.HtmlUnitNYI;
 import org.htmlunit.util.MimeType;
-import org.htmlunit.util.NameValuePair;
 import org.junit.jupiter.api.Test;
 import org.openqa.selenium.WebDriver;
-import org.openqa.selenium.htmlunit.HtmlUnitDriver;
 
 /**
- * Tests for Fetch API.
+ * Tests for fetch api host objects.
  *
  * @author Ronald Brill
  */
@@ -39,779 +31,128 @@ public class FetchTest extends WebDriverTestCase {
      * @throws Exception if the test fails
      */
     @Test
-    @Alerts({"200", "OK", "true", "text/xml;charset=iso-8859-1",
-             "<xml><content>blah</content></xml>"})
-    public void fetchGet() throws Exception {
-        final String html = DOCTYPE_HTML
-            + "<html>\n"
-            + "  <body>\n"
-            + "    <script>\n"
-            + LOG_TITLE_FUNCTION_NORMALIZE
-            + "      fetch('" + URL_SECOND + "')\n"
-            + "        .then(response => {\n"
-            + "          log(response.status);\n"
-            + "          log(response.statusText);\n"
-            + "          log(response.ok);\n"
-            + "          log(response.headers.get('content-type'));\n"
-            + "          return response.text();"
-            + "         })\n"
-            + "        .then(text => log(text))\n"
-            + "        .catch(e => logEx(e));\n"
-            + "    </script>\n"
-            + "  </body>\n"
-            + "</html>";
-
-        final String xml = "<xml><content>blah</content></xml>";
-        getMockWebConnection().setResponse(URL_SECOND, xml, MimeType.TEXT_XML);
-
-        final WebDriver driver = enableFetchPolyfill();
-        loadPage2(html);
-        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-
-        assertEquals(URL_SECOND, getMockWebConnection().getLastWebRequest().getUrl());
-    }
-
-    /**
-     * @throws Exception if the test fails
-     */
-    @Test
-    @Alerts("TypeError")
-    public void fetchGetWithBody() throws Exception {
+    @Alerts({"function", "function", "function", "function"})
+    public void globalsAvailable() throws Exception {
         final String html = DOCTYPE_HTML
-            + "<html>\n"
-            + "  <body>\n"
-            + "    <script>\n"
+            + "<html><head><script>\n"
             + LOG_TITLE_FUNCTION
-            + "      fetch('" + URL_SECOND + "', {\n"
-            + "        method: 'GET',\n"
-            + "        body: 'test data'\n"
-            + "      })\n"
-            + "        .then(response => {\n"
-            + "          log(response.status);\n"
-            + "          log(response.statusText);\n"
-            + "          log(response.ok);\n"
-            + "          log(response.headers.get('content-type'));\n"
-            + "          return response.text();"
-            + "         })\n"
-            + "        .then(text => log(text))\n"
-            + "        .catch(e => logEx(e));\n"
-            + "    </script>\n"
-            + "  </body>\n"
-            + "</html>";
+            + "  log(typeof fetch);\n"
+            + "  log(typeof Headers);\n"
+            + "  log(typeof Request);\n"
+            + "  log(typeof Response);\n"
+            + "</script></head><body></body></html>";
 
-        getMockWebConnection().setResponse(URL_SECOND, "<response/>", MimeType.TEXT_XML);
-
-        final WebDriver driver = enableFetchPolyfill();
-        loadPage2(html);
-        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-
-        assertEquals(URL_FIRST, getMockWebConnection().getLastWebRequest().getUrl());
+        loadPageVerifyTitle2(html);
     }
 
     /**
      * @throws Exception if the test fails
      */
     @Test
-    @Alerts("TypeError")
-    public void fetchGetWrongUrl() throws Exception {
+    @Alerts({"200", "OK", "true", URL_SECOND + "", "basic", "payload"})
+    public void fetchGet() throws Exception {
         final String html = DOCTYPE_HTML
-            + "<html>\n"
-            + "  <body>\n"
-            + "    <script>\n"
+            + "<html><body><script>\n"
             + LOG_TITLE_FUNCTION
-            + "      fetch('https://this.does.not.exist/htmlunit')\n"
-            + "        .then(response => {\n"
-            + "          log(response.status);\n"
-            + "          log(response.statusText);\n"
-            + "          log(response.ok);\n"
-            + "          log(response.headers.get('content-type'));\n"
-            + "          return response.text();"
-            + "         })\n"
-            + "        .then(text => log(text))\n"
-            + "        .catch(e => logEx(e));\n"
-            + "    </script>\n"
-            + "  </body>\n"
-            + "</html>";
-
-        getMockWebConnection().setResponse(URL_SECOND, "<response/>", MimeType.TEXT_XML);
-
-        final WebDriver driver = enableFetchPolyfill();
-        loadPage2(html);
-        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-
-        assertEquals(1, getMockWebConnection().getRequestCount());
-    }
-
-    /**
-     * Tests fetch with different HTTP methods.
-     * @throws Exception if the test fails
-     */
-    @Test
-    @Alerts({"200", "OK", "true", "text/xml;charset=iso-8859-1", "<response/>"})
-    public void fetchPost() throws Exception {
-        final String html = DOCTYPE_HTML
-            + "<html>\n"
-            + "  <body>\n"
-            + "    <script>\n"
-            + LOG_TITLE_FUNCTION_NORMALIZE
-            + "      fetch('" + URL_SECOND + "', {\n"
-            + "        method: 'POST',\n"
-            + "        body: 'test data'\n"
-            + "      })\n"
-            + "        .then(response => {\n"
-            + "          log(response.status);\n"
-            + "          log(response.statusText);\n"
-            + "          log(response.ok);\n"
-            + "          log(response.headers.get('content-type'));\n"
-            + "          return response.text();"
-            + "         })\n"
-            + "        .then(text => log(text))\n"
-            + "        .catch(e => logEx(e));\n"
-            + "    </script>\n"
-            + "  </body>\n"
-            + "</html>";
-
-        getMockWebConnection().setResponse(URL_SECOND, "<response/>", MimeType.TEXT_XML);
-
-        final WebDriver driver = enableFetchPolyfill();
-        loadPage2(html);
+            + "  fetch('" + URL_SECOND + "')\n"
+            + "    .then(r => {\n"
+            + "      log(r.status);\n"
+            + "      log(r.statusText);\n"
+            + "      log(r.ok);\n"
+            + "      log(r.url);\n"
+            + "      log(r.type);\n"
+            + "      return r.text();\n"
+            + "    })\n"
+            + "    .then(t => log(t))\n"
+            + "    .catch(e => log(e.name));\n"
+            + "</script></body></html>";
+
+        getMockWebConnection().setResponse(URL_SECOND, "payload", MimeType.TEXT_PLAIN);
+        final WebDriver driver = loadPage2(html);
         verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-
-        assertEquals(URL_SECOND, getMockWebConnection().getLastWebRequest().getUrl());
-        assertEquals("test data", getMockWebConnection().getLastWebRequest().getRequestBody());
     }
 
     /**
      * @throws Exception if the test fails
      */
     @Test
-    @Alerts({"200", "OK", "true",
-             "text/plain;charset=iso-8859-1", "bla\\sbla"})
-    public void fetchGetText() throws Exception {
+    @Alerts({"404", "false"})
+    public void fetchStatus() throws Exception {
         final String html = DOCTYPE_HTML
-            + "<html>\n"
-            + "  <body>\n"
-            + "    <script>\n"
-            + LOG_TITLE_FUNCTION_NORMALIZE
-            + "      fetch('" + URL_SECOND + "')\n"
-            + "        .then(response => {\n"
-            + "          log(response.status);\n"
-            + "          log(response.statusText);\n"
-            + "          log(response.ok);\n"
-            + "          log(response.headers.get('content-type'));\n"
-            + "          return response.text();"
-            + "         })\n"
-            + "        .then(text => log(text))\n"
-            + "        .catch(e => logEx(e));\n"
-            + "    </script>\n"
-            + "  </body>\n"
-            + "</html>";
-
-        getMockWebConnection().setResponse(URL_SECOND, "bla bla", MimeType.TEXT_PLAIN);
-
-        final WebDriver driver = enableFetchPolyfill();
-        loadPage2(html);
-        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-
-        assertEquals(URL_SECOND, getMockWebConnection().getLastWebRequest().getUrl());
-    }
-
-    /**
-     * @throws Exception if the test fails
-     */
-    @Test
-    @Alerts({"200", "OK", "true",
-             "application/json;charset=iso-8859-1", "{\\s'Html':\\s'Unit'\\s}"})
-    public void fetchGetJsonText() throws Exception {
-        final String html = DOCTYPE_HTML
-            + "<html>\n"
-            + "  <body>\n"
-            + "    <script>\n"
-            + LOG_TITLE_FUNCTION_NORMALIZE
-            + "      fetch('" + URL_SECOND + "')\n"
-            + "        .then(response => {\n"
-            + "          log(response.status);\n"
-            + "          log(response.statusText);\n"
-            + "          log(response.ok);\n"
-            + "          log(response.headers.get('content-type'));\n"
-            + "          return response.text();"
-            + "         })\n"
-            + "        .then(text => log(text))\n"
-            + "        .catch(e => logEx(e));\n"
-            + "    </script>\n"
-            + "  </body>\n"
-            + "</html>";
-
-        final String json = "{ 'Html': 'Unit' }";
-        getMockWebConnection().setResponse(URL_SECOND, json, MimeType.APPLICATION_JSON);
-
-        final WebDriver driver = enableFetchPolyfill();
-        loadPage2(html);
-        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-
-        assertEquals(URL_SECOND, getMockWebConnection().getLastWebRequest().getUrl());
-    }
-
-    /**
-     * @throws Exception if the test fails
-     */
-    @Test
-    @Alerts({"200", "OK", "true",
-             "application/json;charset=iso-8859-1",
-             "[object\\sObject]", "Unit", "{\"Html\":\"Unit\"}"})
-    public void fetchGetJson() throws Exception {
-        final String html = DOCTYPE_HTML
-            + "<html>\n"
-            + "  <body>\n"
-            + "    <script>\n"
-            + LOG_TITLE_FUNCTION_NORMALIZE
-            + "      fetch('" + URL_SECOND + "')\n"
-            + "        .then(response => {\n"
-            + "          log(response.status);\n"
-            + "          log(response.statusText);\n"
-            + "          log(response.ok);\n"
-            + "          log(response.headers.get('content-type'));\n"
-            + "          return response.json();"
-            + "         })\n"
-            + "        .then(json => {\n"
-            + "          log(json);\n"
-            + "          log(json.Html);\n"
-            + "          log(JSON.stringify(json));\n"
-            + "        })\n"
-            + "        .catch(e => logEx(e));\n"
-            + "    </script>\n"
-            + "  </body>\n"
-            + "</html>";
-
-        final String json = "{ \"Html\": \"Unit\" }";
-        getMockWebConnection().setResponse(URL_SECOND, json, MimeType.APPLICATION_JSON);
-
-        final WebDriver driver = enableFetchPolyfill();
-        loadPage2(html);
-        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-
-        assertEquals(URL_SECOND, getMockWebConnection().getLastWebRequest().getUrl());
-    }
-
-    /**
-     * @throws Exception if the test fails
-     */
-    @Test
-    @Alerts(DEFAULT = {"200", "OK", "true", "text/plain;charset=iso-8859-1",
-                       "[object\\sBlob]", "4", "text/plain"},
-            FF = {"200", "OK", "true", "text/plain;charset=iso-8859-1",
-                  "[object\\sBlob]", "4", "text/plain;charset=iso-8859-1"},
-            FF_ESR = {"200", "OK", "true", "text/plain;charset=iso-8859-1",
-                      "[object\\sBlob]", "4", "text/plain;charset=iso-8859-1"})
-    @HtmlUnitNYI(
-            FF = {"200", "OK", "true", "text/plain;charset=iso-8859-1",
-                  "[object\\sBlob]", "4", "text/plain"},
-            FF_ESR = {"200", "OK", "true", "text/plain;charset=iso-8859-1",
-                      "[object\\sBlob]", "4", "text/plain"})
-    public void fetchGetBlob() throws Exception {
-        final String html = DOCTYPE_HTML
-            + "<html>\n"
-            + "  <body>\n"
-            + "    <script>\n"
-            + LOG_TITLE_FUNCTION_NORMALIZE
-            + "      fetch('" + URL_SECOND + "')\n"
-            + "        .then(response => {\n"
-            + "          log(response.status);\n"
-            + "          log(response.statusText);\n"
-            + "          log(response.ok);\n"
-            + "          log(response.headers.get('content-type'));\n"
-            + "          return response.blob();"
-            + "         })\n"
-            + "        .then(blob => {\n"
-            + "          log(blob);\n"
-            + "          log(blob.size);\n"
-            + "          log(blob.type);\n"
-            + "        })\n"
-            + "        .catch(e => logEx(e));\n"
-            + "    </script>\n"
-            + "  </body>\n"
-            + "</html>";
-
-        getMockWebConnection().setResponse(URL_SECOND, "ABCD", MimeType.TEXT_PLAIN);
-
-        final WebDriver driver = enableFetchPolyfill();
-        loadPage2(html);
-        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-
-        assertEquals(URL_SECOND, getMockWebConnection().getLastWebRequest().getUrl());
-    }
-
-    /**
-     * @throws Exception if the test fails
-     */
-    @Test
-    @Alerts({"200", "OK", "true", "text/plain;charset=iso-8859-1",
-             "[object\\sArrayBuffer]", "4"})
-    public void fetchGetArrayBuffer() throws Exception {
-        final String html = DOCTYPE_HTML
-            + "<html>\n"
-            + "  <body>\n"
-            + "    <script>\n"
-            + LOG_TITLE_FUNCTION_NORMALIZE
-            + "      fetch('" + URL_SECOND + "')\n"
-            + "        .then(response => {\n"
-            + "          log(response.status);\n"
-            + "          log(response.statusText);\n"
-            + "          log(response.ok);\n"
-            + "          log(response.headers.get('content-type'));\n"
-            + "          return response.arrayBuffer();"
-            + "         })\n"
-            + "        .then(buffer => {\n"
-            + "          log(buffer);\n"
-            + "          log(buffer.byteLength);\n"
-            + "        })\n"
-            + "        .catch(e => logEx(e));\n"
-            + "    </script>\n"
-            + "  </body>\n"
-            + "</html>";
-
-        getMockWebConnection().setResponse(URL_SECOND, "ABCD", MimeType.TEXT_PLAIN);
-
-        final WebDriver driver = enableFetchPolyfill();
-        loadPage2(html);
-        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-
-        assertEquals(URL_SECOND, getMockWebConnection().getLastWebRequest().getUrl());
-    }
-
-    /**
-     * @throws Exception if the test fails
-     */
-    @Test
-    @Alerts({"200", "OK", "true"})
-    public void fetchGetCustomHeader() throws Exception {
-        final String html = DOCTYPE_HTML
-            + "<html>\n"
-            + "  <body>\n"
-            + "    <script>\n"
-            + LOG_TITLE_FUNCTION_NORMALIZE
-            + "      fetch('" + URL_SECOND + "', {\n"
-            + "        method: 'GET',\n"
-            + "        headers: {\n"
-            + "          'Content-Type': 'application/json',\n"
-            + "          'X-Custom-Header': 'x-test'\n"
-            + "        }\n"
-            + "      })"
-            + "        .then(response => {\n"
-            + "          log(response.status);\n"
-            + "          log(response.statusText);\n"
-            + "          log(response.ok);\n"
-            + "         })\n"
-            + "        .catch(e => logEx(e));\n"
-            + "    </script>\n"
-            + "  </body>\n"
-            + "</html>";
-
-        final String json = "{ \"Html\": \"Unit\" }";
-        getMockWebConnection().setResponse(URL_SECOND, json, MimeType.APPLICATION_JSON);
-
-        final WebDriver driver = enableFetchPolyfill();
-        loadPage2(html);
-        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-
-        final WebRequest lastRequest = getMockWebConnection().getLastWebRequest();
-        assertEquals(URL_SECOND, lastRequest.getUrl());
-
-        assertEquals("x-test", lastRequest.getAdditionalHeader("X-Custom-Header"));
-    }
-
-    /**
-     * @throws Exception if the test fails
-     */
-    @Test
-    @Alerts({"200", "OK", "true", "text/plain;charset=iso-8859-1", "x-tEsT"})
-    public void fetchGetCustomResponseHeader() throws Exception {
-        final String html = DOCTYPE_HTML
-            + "<html>\n"
-            + "  <body>\n"
-            + "    <script>\n"
-            + LOG_TITLE_FUNCTION_NORMALIZE
-            + "      fetch('" + URL_SECOND + "', {\n"
-            + "        method: 'GET',\n"
-            + "        headers: {\n"
-            + "          'Content-Type': 'application/json',\n"
-            + "          'X-Custom-Header': 'x-test'\n"
-            + "        }\n"
-            + "      })"
-            + "        .then(response => {\n"
-            + "          log(response.status);\n"
-            + "          log(response.statusText);\n"
-            + "          log(response.ok);\n"
-            + "          log(response.headers.get('content-type'));\n"
-            + "          log(response.headers.get('X-Custom-Header'));\n"
-            + "         })\n"
-            + "        .catch(e => logEx(e));\n"
-            + "    </script>\n"
-            + "  </body>\n"
-            + "</html>";
-
-        final List<NameValuePair> headers = new ArrayList<>();
-        headers.add(new NameValuePair("X-Custom-Header", "x-tEsT"));
-        getMockWebConnection().setResponse(URL_SECOND, "HtmlUnit", 200, "ok", MimeType.TEXT_PLAIN, headers);
+            + "<html><body><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  fetch('" + URL_SECOND + "')\n"
+            + "    .then(r => { log(r.status); log(r.ok); })\n"
+            + "    .catch(e => log(e.name));\n"
+            + "</script></body></html>";
 
-        final WebDriver driver = enableFetchPolyfill();
-        loadPage2(html);
+        getMockWebConnection().setResponse(URL_SECOND, "missing", 404, "Not Found", MimeType.TEXT_PLAIN);
+        final WebDriver driver = loadPage2(html);
         verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-
-        final WebRequest lastRequest = getMockWebConnection().getLastWebRequest();
-        assertEquals(URL_SECOND, lastRequest.getUrl());
-
-        assertEquals("x-test", lastRequest.getAdditionalHeader("X-Custom-Header"));
     }
 
     /**
      * @throws Exception if the test fails
      */
     @Test
-    @Alerts({"200", "OK", "true"})
-    public void fetchPostFormData() throws Exception {
+    @Alerts({"200", "true", "HtmlUnit"})
+    public void fetchPostJson() throws Exception {
         final String html = DOCTYPE_HTML
-            + "<html>\n"
-            + "  <body>\n"
-
-            + "    <form name='testForm'>\n"
-            + "      <input type='text' name='myText' value='HtmlUnit'>\n"
-            + "    </form>\n"
-
-            + "    <script>\n"
-            + LOG_TITLE_FUNCTION_NORMALIZE
-            + "      let formData = new FormData(document.testForm);"
-
-            + "      fetch('" + URL_SECOND + "', {\n"
-            + "        method: 'POST',\n"
-            + "        body: formData\n"
-            + "      })"
-            + "        .then(response => {\n"
-            + "          log(response.status);\n"
-            + "          log(response.statusText);\n"
-            + "          log(response.ok);\n"
-            + "         })\n"
-            + "        .catch(e => logEx(e));\n"
-            + "    </script>\n"
-            + "  </body>\n"
-            + "</html>";
+            + "<html><body><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  fetch('" + URL_SECOND + "', {\n"
+            + "    method: 'POST',\n"
+            + "    headers: {'Content-Type': 'application/json'},\n"
+            + "    body: JSON.stringify({q: 'HtmlUnit'})\n"
+            + "  })\n"
+            + "   .then(r => { log(r.status); log(r.ok); return r.text(); })\n"
+            + "   .then(t => log(t))\n"
+            + "   .catch(e => log(e.name));\n"
+            + "</script></body></html>";
 
         getMockWebConnection().setResponse(URL_SECOND, "HtmlUnit", MimeType.TEXT_PLAIN);
-
-        final WebDriver driver = enableFetchPolyfill();
-        loadPage2(html);
-        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-
-        final WebRequest lastRequest = getMockWebConnection().getLastWebRequest();
-        assertEquals(URL_SECOND, lastRequest.getUrl());
-
-        assertTrue(lastRequest.getRequestBody(), lastRequest.getRequestBody()
-                                .contains("Content-Disposition: form-data; name=\"myText\""));
-        assertTrue(lastRequest.getRequestBody(), lastRequest.getRequestBody()
-                .contains("HtmlUnit"));
-    }
-
-    /**
-     * @throws Exception if the test fails
-     */
-    @Test
-    @Alerts({"200", "OK", "true", "test0,Hello1\\nHello1,test1,Hello2\\nHello2"})
-    public void fetchMultipartFormData() throws Exception {
-        final String html = DOCTYPE_HTML
-                + "<html>\n"
-                + "  <body>\n"
-                + "    <script>\n"
-                + LOG_TITLE_FUNCTION_NORMALIZE
-                + "      fetch('" + URL_SECOND + "')"
-                + "        .then(response => {\n"
-                + "          log(response.status);\n"
-                + "          log(response.statusText);\n"
-                + "          log(response.ok);\n"
-
-                + "          return response.formData();\n"
-                + "        })\n"
-                + "        .then(formData => {\n"
-                + "            log(Array.from(formData.entries()));\n"
-                + "        })\n"
-                + "        .catch(e => log(e.message));\n"
-                + "    </script>\n"
-                + "  </body>\n"
-                + "</html>";
-
-        final String boundary = "0123456789";
-        final String content = "--" + boundary + "\r\n"
-                + "Content-Disposition: form-data; name=\"test0\"\r\n"
-                + "Content-Type: text/plain\r\n"
-                + "\r\n"
-                + "Hello1\nHello1\r\n"
-                + "--" + boundary + "\r\n"
-                + "Content-Disposition: form-data; name=\"test1\"\r\n"
-                + "Content-Type: text/plain\r\n"
-                + "\r\n"
-                + "Hello2\nHello2\r\n"
-                + "--" + boundary + "--";
-
-        getMockWebConnection().setResponse(URL_SECOND, content, "multipart/form-data; boundary=" + boundary);
-
-        final WebDriver driver = enableFetchPolyfill();
-        loadPage2(html);
+        final WebDriver driver = loadPage2(html);
         verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-
-        assertEquals(URL_SECOND, getMockWebConnection().getLastWebRequest().getUrl());
     }
 
     /**
      * @throws Exception if the test fails
      */
     @Test
-    @Alerts({"200", "OK", "true"})
-    public void fetchPostURLSearchParams() throws Exception {
+    @Alerts("TypeError")
+    public void fetchInvalidUrlRejects() throws Exception {
         final String html = DOCTYPE_HTML
-            + "<html>\n"
-            + "  <body>\n"
-            + "    <script>\n"
-            + LOG_TITLE_FUNCTION_NORMALIZE
-            + "      let searchParams = new URLSearchParams();\n"
-            + "      searchParams.append('q', 'HtmlUnit');\n"
-            + "      searchParams.append('page', '1');\n"
-            + "      fetch('" + URL_SECOND + "', {\n"
-            + "        method: 'POST',\n"
-            + "        body: searchParams\n"
-            + "      })"
-            + "        .then(response => {\n"
-            + "          log(response.status);\n"
-            + "          log(response.statusText);\n"
-            + "          log(response.ok);\n"
-            + "         })\n"
-            + "        .catch(e => logEx(e));\n"
-            + "    </script>\n"
-            + "  </body>\n"
-            + "</html>";
-
-        getMockWebConnection().setResponse(URL_SECOND, "HtmlUnit", MimeType.TEXT_PLAIN);
+            + "<html><body><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  fetch('ftp://example.com/path')\n"
+            + "   .then(() => log('ok'))\n"
+            + "   .catch(e => log(e.name));\n"
+            + "</script></body></html>";
 
-        final WebDriver driver = enableFetchPolyfill();
-        loadPage2(html);
+        final WebDriver driver = loadPage2(html);
         verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-
-        final WebRequest lastRequest = getMockWebConnection().getLastWebRequest();
-        assertEquals(URL_SECOND, lastRequest.getUrl());
-
-        String headerContentType = lastRequest.getAdditionalHeaders().get(HttpHeader.CONTENT_TYPE);
-        headerContentType = headerContentType.split(";")[0];
-        assertEquals("application/x-www-form-urlencoded", headerContentType);
-
-        final List<NameValuePair> params = lastRequest.getRequestParameters();
-        assertEquals(2, params.size());
-        assertEquals("q", params.get(0).getName());
-        assertEquals("HtmlUnit", params.get(0).getValue());
-        assertEquals("page", params.get(1).getName());
-        assertEquals("1", params.get(1).getValue());
     }
 
     /**
      * @throws Exception if the test fails
      */
     @Test
-    @Alerts({"200", "OK", "true"})
-    public void fetchPostJSON() throws Exception {
+    @Alerts({"200", "ok", "200"})
+    public void fetchThenChainAndAwait() throws Exception {
         final String html = DOCTYPE_HTML
-            + "<html>\n"
-            + "  <body>\n"
-            + "    <script>\n"
-            + LOG_TITLE_FUNCTION_NORMALIZE
-            + "      let jsonData = {hello: 'world'};\n"
-            + "      fetch('" + URL_SECOND + "', {\n"
-            + "        method: 'POST',\n"
-            + "        headers: {\n"
-            + "          'Content-Type': 'application/json'\n"
-            + "        },\n"
-            + "        body: JSON.stringify(jsonData)\n"
-            + "      })"
-            + "        .then(response => {\n"
-            + "          log(response.status);\n"
-            + "          log(response.statusText);\n"
-            + "          log(response.ok);\n"
-            + "         })\n"
-            + "        .catch(e => logEx(e));\n"
-            + "    </script>\n"
-            + "  </body>\n"
-            + "</html>";
-
-        getMockWebConnection().setResponse(URL_SECOND, "HtmlUnit", MimeType.TEXT_PLAIN);
-
-        final WebDriver driver = enableFetchPolyfill();
-        loadPage2(html);
+            + "<html><body><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  fetch('" + URL_SECOND + "')\n"
+            + "    .then(r => r.text())\n"
+            + "    .then(t => log(t));\n"
+            + "  (async function() {\n"
+            + "    const r = await fetch('" + URL_SECOND + "');\n"
+            + "    log(r.status);\n"
+            + "  })();\n"
+            + "</script></body></html>";
+
+        getMockWebConnection().setResponse(URL_SECOND, "ok", MimeType.TEXT_PLAIN);
+        final WebDriver driver = loadPage2(html);
         verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-
-        final WebRequest lastRequest = getMockWebConnection().getLastWebRequest();
-        assertEquals(URL_SECOND, lastRequest.getUrl());
-
-        String headerContentType = lastRequest.getAdditionalHeaders().get(HttpHeader.CONTENT_TYPE);
-        headerContentType = headerContentType.split(";")[0];
-        assertEquals("application/json", headerContentType);
-
-        assertEquals("{\"hello\":\"world\"}", lastRequest.getRequestBody());
-    }
-
-//    /**
-//     * Tests fetch with credentials.
-//     * @throws Exception if the test fails
-//     */
-//    @Test
-//    @Alerts("ok")
-//    public void fetchWithCredentials() throws Exception {
-//        final String html = DOCTYPE_HTML
-//            + "<html><head>\n"
-//            + "<script>\n"
-//            + LOG_TITLE_FUNCTION
-//            + "function test() {\n"
-//            + "  fetch('" + URL_SECOND + "', {\n"
-//            + "    method: 'GET',\n"
-//            + "    credentials: 'include'\n"
-//            + "  })\n"
-//            + "    .then(response => log(response.ok ? 'ok' : 'not ok'))\n"
-//            + "    .catch(e => logEx(e));\n"
-//            + "}\n"
-//            + "</script>\n"
-//            + "</head>\n"
-//            + "<body onload='test()'></body></html>";
-//
-//        getMockWebConnection().setDefaultResponse("<response/>\n", MimeType.TEXT_XML);
-//        final WebDriver driver = loadPage2(html);
-//        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-//    }
-//
-//    /**
-//     * Tests fetch response cloning.
-//     * @throws Exception if the test fails
-//     */
-//    @Test
-//    @Alerts({"true", "text1", "text2"})
-//    public void fetchResponseClone() throws Exception {
-//        final String html = DOCTYPE_HTML
-//            + "<html><head>\n"
-//            + "<script>\n"
-//            + LOG_TITLE_FUNCTION
-//            + "function test() {\n"
-//            + "  fetch('" + URL_SECOND + "')\n"
-//            + "    .then(response => {\n"
-//            + "      var cloned = response.clone();\n"
-//            + "      log(cloned.ok);\n"
-//            + "      return Promise.all([\n"
-//            + "        response.text(),\n"
-//            + "        cloned.text()\n"
-//            + "      ]);\n"
-//            + "    })\n"
-//            + "    .then(texts => {\n"
-//            + "      log('text' + (texts[0] === texts[1] ? '1' : '0'));\n"
-//            + "      log('text2');\n"
-//            + "    })\n"
-//            + "    .catch(e => logEx(e));\n"
-//            + "}\n"
-//            + "</script>\n"
-//            + "</head>\n"
-//            + "<body onload='test()'></body></html>";
-//
-//        getMockWebConnection().setDefaultResponse("response body", MimeType.TEXT_PLAIN);
-//        final WebDriver driver = loadPage2(html);
-//        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-//    }
-//
-//    /**
-//     * Tests fetch with mode option.
-//     * @throws Exception if the test fails
-//     */
-//    @Test
-//    @Alerts("ok")
-//    public void fetchWithMode() throws Exception {
-//        final String html = DOCTYPE_HTML
-//            + "<html><head>\n"
-//            + "<script>\n"
-//            + LOG_TITLE_FUNCTION
-//            + "function test() {\n"
-//            + "  fetch('" + URL_SECOND + "', {\n"
-//            + "    method: 'GET',\n"
-//            + "    mode: 'cors'\n"
-//            + "  })\n"
-//            + "    .then(response => log(response.ok ? 'ok' : 'not ok'))\n"
-//            + "    .catch(e => logEx(e));\n"
-//            + "}\n"
-//            + "</script>\n"
-//            + "</head>\n"
-//            + "<body onload='test()'></body></html>";
-//
-//        getMockWebConnection().setDefaultResponse("<response/>\n", MimeType.TEXT_XML);
-//        final WebDriver driver = loadPage2(html);
-//        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-//    }
-//
-//    /**
-//     * Tests fetch with cache option.
-//     * @throws Exception if the test fails
-//     */
-//    @Test
-//    @Alerts("ok")
-//    public void fetchWithCache() throws Exception {
-//        final String html = DOCTYPE_HTML
-//            + "<html><head>\n"
-//            + "<script>\n"
-//            + LOG_TITLE_FUNCTION
-//            + "function test() {\n"
-//            + "  fetch('" + URL_SECOND + "', {\n"
-//            + "    method: 'GET',\n"
-//            + "    cache: 'no-cache'\n"
-//            + "  })\n"
-//            + "    .then(response => log(response.ok ? 'ok' : 'not ok'))\n"
-//            + "    .catch(e => logEx(e));\n"
-//            + "}\n"
-//            + "</script>\n"
-//            + "</head>\n"
-//            + "<body onload='test()'></body></html>";
-//
-//        getMockWebConnection().setDefaultResponse("<response/>\n", MimeType.TEXT_XML);
-//        final WebDriver driver = loadPage2(html);
-//        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-//    }
-//
-//    /**
-//     * Tests fetch response with text encoding.
-//     * @throws Exception if the test fails
-//     */
-//    @Test
-//    @Alerts("olé")
-//    public void fetchResponseTextEncoding() throws Exception {
-//        final String html = DOCTYPE_HTML
-//            + "<html>\n"
-//            + "  <head>\n"
-//            + "    <script>\n"
-//            + LOG_TITLE_FUNCTION
-//            + "      function test() {\n"
-//            + "        fetch('" + URL_SECOND + "')\n"
-//            + "          .then(response => response.text())\n"
-//            + "          .then(text => log(text))\n"
-//            + "          .catch(e => logEx(e));\n"
-//            + "      }\n"
-//            + "    </script>\n"
-//            + "  </head>\n"
-//            + "  <body onload='test()'>\n"
-//            + "  </body>\n"
-//            + "</html>";
-//
-//        final String response = "olé";
-//        final byte[] responseBytes = response.getBytes(UTF_8);
-//
-//        getMockWebConnection().setResponse(URL_SECOND, responseBytes, 200, "OK",
-//            MimeType.TEXT_HTML, new ArrayList<>());
-//        final WebDriver driver = loadPage2(html);
-//        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
-//    }
-
-    private WebDriver enableFetchPolyfill() {
-        final WebDriver driver = getWebDriver();
-        if (driver instanceof HtmlUnitDriver) {
-            ((HtmlUnitDriver) driver).getWebClient().getOptions().setFetchPolyfillEnabled(true);
-        }
-        return driver;
     }
 }
diff --git a/src/test/java/org/htmlunit/javascript/host/fetch/HeadersTest.java b/src/test/java/org/htmlunit/javascript/host/fetch/HeadersTest.java
new file mode 100644
index 0000000000..ad94ec2635
--- /dev/null
+++ b/src/test/java/org/htmlunit/javascript/host/fetch/HeadersTest.java
@@ -0,0 +1,152 @@
+/*
+ * Copyright (c) 2002-2026 Gargoyle Software Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.htmlunit.javascript.host.fetch;
+
+import org.htmlunit.WebDriverTestCase;
+import org.htmlunit.junit.annotation.Alerts;
+import org.junit.jupiter.api.Test;
+
+/**
+ * Tests for {@link Headers}.
+ *
+ * @author Ronald Brill
+ */
+public class HeadersTest extends WebDriverTestCase {
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    @Alerts({"0", "false"})
+    public void constructorEmpty() throws Exception {
+        final String html = DOCTYPE_HTML
+            + "<html><head><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  const h = new Headers();\n"
+            + "  log(Array.from(h.entries()).length);\n"
+            + "  log(h.has('x-test'));\n"
+            + "</script></head><body></body></html>";
+
+        loadPageVerifyTitle2(html);
+    }
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    @Alerts({"v1", "v2", "v3", "v4", "v5"})
+    public void constructorFromObjectSequenceAndHeaders() throws Exception {
+        final String html = DOCTYPE_HTML
+            + "<html><head><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  const h1 = new Headers({'A': 'v1'});\n"
+            + "  const h2 = new Headers([['B', 'v2'], ['C', 'v3']]);\n"
+            + "  const h3 = new Headers(h1);\n"
+            + "  h3.append('d', 'v4');\n"
+            + "  const h4 = new Headers(h3);\n"
+            + "  h4.set('d', 'v5');\n"
+            + "  log(h1.get('a'));\n"
+            + "  log(h2.get('b'));\n"
+            + "  log(h2.get('c'));\n"
+            + "  log(h3.get('d'));\n"
+            + "  log(h4.get('d'));\n"
+            + "</script></head><body></body></html>";
+
+        loadPageVerifyTitle2(html);
+    }
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    @Alerts({"v1, v2", "true", "v3", "false"})
+    public void appendSetHasDeleteCaseInsensitive() throws Exception {
+        final String html = DOCTYPE_HTML
+            + "<html><head><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  const h = new Headers();\n"
+            + "  h.append('X-Test', 'v1');\n"
+            + "  h.append('x-test', 'v2');\n"
+            + "  log(h.get('X-TEST'));\n"
+            + "  log(h.has('x-Test'));\n"
+            + "  h.set('x-test', 'v3');\n"
+            + "  log(h.get('X-TEST'));\n"
+            + "  h.delete('X-tEsT');\n"
+            + "  log(h.has('x-test'));\n"
+            + "</script></head><body></body></html>";
+
+        loadPageVerifyTitle2(html);
+    }
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    @Alerts({"a=1,b=2", "a,b", "1,2", "a:1|b:2", "a=1,b=2"})
+    public void iteratorsAndForEach() throws Exception {
+        final String html = DOCTYPE_HTML
+            + "<html><head><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  const h = new Headers([['a', '1'], ['b', '2']]);\n"
+            + "  log(Array.from(h.entries()).map(e => e[0] + '=' + e[1]).join(','));\n"
+            + "  log(Array.from(h.keys()).join(','));\n"
+            + "  log(Array.from(h.values()).join(','));\n"
+            + "  let s = [];\n"
+            + "  h.forEach((v, k) => s.push(k + ':' + v));\n"
+            + "  log(s.join('|'));\n"
+            + "  log(Array.from(h).map(e => e[0] + '=' + e[1]).join(','));\n"
+            + "</script></head><body></body></html>";
+
+        loadPageVerifyTitle2(html);
+    }
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    @Alerts({"2", "c1", "c2"})
+    public void getSetCookie() throws Exception {
+        final String html = DOCTYPE_HTML
+            + "<html><head><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  const h = new Headers();\n"
+            + "  h.append('Set-Cookie', 'c1');\n"
+            + "  h.append('set-cookie', 'c2');\n"
+            + "  const c = h.getSetCookie();\n"
+            + "  log(c.length);\n"
+            + "  log(c[0]);\n"
+            + "  log(c[1]);\n"
+            + "</script></head><body></body></html>";
+
+        loadPageVerifyTitle2(html);
+    }
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    @Alerts("TypeError")
+    public void constructorInvalid() throws Exception {
+        final String html = DOCTYPE_HTML
+            + "<html><head><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  try {\n"
+            + "    new Headers(1);\n"
+            + "  } catch (e) { log(e.name); }\n"
+            + "</script></head><body></body></html>";
+
+        loadPageVerifyTitle2(html);
+    }
+}
diff --git a/src/test/java/org/htmlunit/javascript/host/fetch/RequestTest.java b/src/test/java/org/htmlunit/javascript/host/fetch/RequestTest.java
new file mode 100644
index 0000000000..e5f1c783f5
--- /dev/null
+++ b/src/test/java/org/htmlunit/javascript/host/fetch/RequestTest.java
@@ -0,0 +1,183 @@
+/*
+ * Copyright (c) 2002-2026 Gargoyle Software Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.htmlunit.javascript.host.fetch;
+
+import org.htmlunit.WebDriverTestCase;
+import org.htmlunit.junit.annotation.Alerts;
+import org.junit.jupiter.api.Test;
+import org.openqa.selenium.WebDriver;
+
+/**
+ * Tests for {@link Request}.
+ *
+ * @author Ronald Brill
+ */
+public class RequestTest extends WebDriverTestCase {
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    @Alerts({"GET", URL_SECOND + "", "cors", "same-origin", "default", "follow", "about:client", "", "", "false"})
+    public void constructorSimple() throws Exception {
+        final String html = DOCTYPE_HTML
+            + "<html><head><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  const req = new Request('" + URL_SECOND + "');\n"
+            + "  log(req.method);\n"
+            + "  log(req.url);\n"
+            + "  log(req.mode);\n"
+            + "  log(req.credentials);\n"
+            + "  log(req.cache);\n"
+            + "  log(req.redirect);\n"
+            + "  log(req.referrer);\n"
+            + "  log(req.referrerPolicy);\n"
+            + "  log(req.integrity);\n"
+            + "  log(req.keepalive);\n"
+            + "</script></head><body></body></html>";
+
+        loadPageVerifyTitle2(html);
+    }
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    @Alerts({"POST", "v", "false", "cors", "include", "no-cache", "manual", "",
+        "strict-origin", "abc", "true", "true", "body"})
+    public void constructorWithInit() throws Exception {
+        final String html = DOCTYPE_HTML
+            + "<html><head><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  const sig = new AbortController().signal;\n"
+            + "  const req = new Request('" + URL_SECOND + "', {\n"
+            + "    method: 'post',\n"
+            + "    headers: {'x-a': 'v'},\n"
+            + "    body: 'body',\n"
+            + "    mode: 'cors',\n"
+            + "    credentials: 'include',\n"
+            + "    cache: 'no-cache',\n"
+            + "    redirect: 'manual',\n"
+            + "    referrer: '',\n"
+            + "    referrerPolicy: 'strict-origin',\n"
+            + "    integrity: 'abc',\n"
+            + "    keepalive: true,\n"
+            + "    signal: sig\n"
+            + "  });\n"
+            + "  log(req.method);\n"
+            + "  log(req.headers.get('x-a'));\n"
+            + "  log(req.bodyUsed);\n"
+            + "  log(req.mode);\n"
+            + "  log(req.credentials);\n"
+            + "  log(req.cache);\n"
+            + "  log(req.redirect);\n"
+            + "  log(req.referrer);\n"
+            + "  log(req.referrerPolicy);\n"
+            + "  log(req.integrity);\n"
+            + "  log(req.keepalive);\n"
+            + "  log(req.signal === sig);\n"
+            + "  req.text().then(t => log(t));\n"
+            + "</script></head><body></body></html>";
+
+        final WebDriver driver = loadPage2(html);
+        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
+    }
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    @Alerts({"POST", "x", "true", "false", "x"})
+    public void constructorFromRequestAndClone() throws Exception {
+        final String html = DOCTYPE_HTML
+            + "<html><head><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  const base = new Request('" + URL_SECOND + "', {method: 'POST', headers: {'x-a': 'x'}, body: 'x'});\n"
+            + "  const req = new Request(base);\n"
+            + "  const clone = req.clone();\n"
+            + "  log(req.method);\n"
+            + "  log(req.headers.get('x-a'));\n"
+            + "  log(req.url === base.url);\n"
+            + "  log(req === clone);\n"
+            + "  clone.text().then(t => log(t));\n"
+            + "</script></head><body></body></html>";
+
+        final WebDriver driver = loadPage2(html);
+        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
+    }
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    @Alerts({"false", "abc", "true", "TypeError"})
+    public void bodyUsed() throws Exception {
+        final String html = DOCTYPE_HTML
+            + "<html><head><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  const req = new Request('" + URL_SECOND + "', {method: 'POST', body: 'abc'});\n"
+            + "  log(req.bodyUsed);\n"
+            + "  req.text()\n"
+            + "    .then(t => { log(t); log(req.bodyUsed); return req.text(); })\n"
+            + "    .catch(e => log(e.name));\n"
+            + "</script></head><body></body></html>";
+
+        final WebDriver driver = loadPage2(html);
+        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
+    }
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    @Alerts({"1", "3", "3", "1", "v", "x"})
+    public void bodyMethods() throws Exception {
+        final String html = DOCTYPE_HTML
+            + "<html><head><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  Promise.resolve()\n"
+            + "      .then(() => new Request('" + URL_SECOND + "', {method: 'POST', body: '{\"a\":1}'}).json())\n"
+            + "      .then(v => { log(v.a); return new Request('" + URL_SECOND + "', {method: 'POST', body: 'abc'}).arrayBuffer(); })\n"
+            + "      .then(b => { log(b.byteLength); return new Request('" + URL_SECOND + "', {method: 'POST', body: 'abc'}).blob(); })\n"
+            + "      .then(b => { log(b.size); return new Request('" + URL_SECOND + "', {method: 'POST', body: 'x'}).clone().text(); })\n"
+            + "      .then(t => {\n"
+            + "          log(t.length);\n"
+            + "          return new Request('" + URL_SECOND + "', {method: 'POST', body: 'q=v&x=y',\n"
+            + "              headers: {'content-type': 'application/x-www-form-urlencoded'}}).formData();\n"
+            + "      })\n"
+            + "      .then(f => { log(f.get('q')); log(f.get('x')); });\n"
+            + "</script></head><body></body></html>";
+
+        final WebDriver driver = loadPage2(html);
+        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
+    }
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    @Alerts({"TypeError", "TypeError"})
+    public void invalidConstructionCases() throws Exception {
+        final String html = DOCTYPE_HTML
+            + "<html><head><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  try { new Request(); log('ok'); } catch (e) { log(e.name); }\n"
+            + "  try { new Request('" + URL_SECOND + "', {method: 'GET', body: 'x'}); log('ok'); }\n"
+            + "  catch (e) { log(e.name); }\n"
+            + "</script></head><body></body></html>";
+
+        loadPageVerifyTitle2(html);
+    }
+}
diff --git a/src/test/java/org/htmlunit/javascript/host/fetch/ResponseTest.java b/src/test/java/org/htmlunit/javascript/host/fetch/ResponseTest.java
new file mode 100644
index 0000000000..81fc4df48e
--- /dev/null
+++ b/src/test/java/org/htmlunit/javascript/host/fetch/ResponseTest.java
@@ -0,0 +1,165 @@
+/*
+ * Copyright (c) 2002-2026 Gargoyle Software Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.htmlunit.javascript.host.fetch;
+
+import org.htmlunit.WebDriverTestCase;
+import org.htmlunit.junit.annotation.Alerts;
+import org.junit.jupiter.api.Test;
+import org.openqa.selenium.WebDriver;
+
+/**
+ * Tests for {@link Response}.
+ *
+ * @author Ronald Brill
+ */
+public class ResponseTest extends WebDriverTestCase {
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    @Alerts({"200", "", "true", "default", "", "false", "false"})
+    public void constructorEmpty() throws Exception {
+        final String html = DOCTYPE_HTML
+            + "<html><head><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  const r = new Response();\n"
+            + "  log(r.status);\n"
+            + "  log(r.statusText);\n"
+            + "  log(r.ok);\n"
+            + "  log(r.type);\n"
+            + "  log(r.url);\n"
+            + "  log(r.redirected);\n"
+            + "  log(r.bodyUsed);\n"
+            + "</script></head><body></body></html>";
+
+        loadPageVerifyTitle2(html);
+    }
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    @Alerts({"201", "Created", "true", "v", "text"})
+    public void constructorBodyAndInit() throws Exception {
+        final String html = DOCTYPE_HTML
+            + "<html><head><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  const r = new Response('text', {\n"
+            + "    status: 201,\n"
+            + "    statusText: 'Created',\n"
+            + "    headers: {'x-a': 'v'}\n"
+            + "  });\n"
+            + "  log(r.status);\n"
+            + "  log(r.statusText);\n"
+            + "  log(r.ok);\n"
+            + "  log(r.headers.get('x-a'));\n"
+            + "  r.text().then(t => log(t));\n"
+            + "</script></head><body></body></html>";
+
+        final WebDriver driver = loadPage2(html);
+        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
+    }
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    @Alerts({"object", "1", "3", "3", "v", "y"})
+    public void bodyMethods() throws Exception {
+        final String html = DOCTYPE_HTML
+            + "<html><head><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  Promise.resolve()\n"
+            + "    .then(() => new Response('{\"a\":1}').json())\n"
+            + "    .then(v => log(typeof v))\n"
+            + "    .then(() => new Response('{\"a\":1}').json())\n"
+            + "    .then(v => log(v.a))\n"
+            + "    .then(() => new Response('abc').arrayBuffer())\n"
+            + "    .then(b => log(b.byteLength))\n"
+            + "    .then(() => new Response('abc').blob())\n"
+            + "    .then(b => log(b.size))\n"
+            + "    .then(() => new Response('q=v&x=y',\n"
+            + "      {headers: {'content-type': 'application/x-www-form-urlencoded'}}).formData())\n"
+            + "    .then(f => { log(f.get('q')); log(f.get('x')); });\n"
+            + "</script></head><body></body></html>";
+
+        final WebDriver driver = loadPage2(html);
+        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
+    }
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    @Alerts({"false", "abc", "true", "TypeError"})
+    public void bodyUsed() throws Exception {
+        final String html = DOCTYPE_HTML
+            + "<html><head><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  const r = new Response('abc');\n"
+            + "  log(r.bodyUsed);\n"
+            + "  r.text()\n"
+            + "    .then(t => { log(t); log(r.bodyUsed); return r.text(); })\n"
+            + "    .catch(e => log(e.name));\n"
+            + "</script></head><body></body></html>";
+
+        final WebDriver driver = loadPage2(html);
+        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
+    }
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    @Alerts({"true", "abc", "abc"})
+    public void clone() throws Exception {
+        final String html = DOCTYPE_HTML
+            + "<html><head><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  const r = new Response('abc');\n"
+            + "  const c = r.clone();\n"
+            + "  log(r !== c);\n"
+            + "  Promise.all([r.text(), c.text()]).then(v => { log(v[0]); log(v[1]); });\n"
+            + "</script></head><body></body></html>";
+
+        final WebDriver driver = loadPage2(html);
+        verifyTitle2(DEFAULT_WAIT_TIME, driver, getExpectedAlerts());
+    }
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    @Alerts({"200", "true", "0", "error", "301", "/a", "302"})
+    public void staticMethods() throws Exception {
+        final String html = DOCTYPE_HTML
+            + "<html><head><script>\n"
+            + LOG_TITLE_FUNCTION
+            + "  const ok = new Response();\n"
+            + "  log(ok.status);\n"
+            + "  log(ok.ok);\n"
+            + "  const err = Response.error();\n"
+            + "  log(err.status);\n"
+            + "  log(err.type);\n"
+            + "  const redir = Response.redirect('/a', 301);\n"
+            + "  log(redir.status);\n"
+            + "  log(redir.headers.get('location'));\n"
+            + "  log(Response.redirect('/b').status);\n"
+            + "</script></head><body></body></html>";
+
+        loadPageVerifyTitle2(html);
+    }
+}