diff --git a/src/PlaywrightNative.Tests/Page/PageTransition/PageTransitionTests.cs b/src/PlaywrightNative.Tests/Page/PageTransition/PageTransitionTests.cs
new file mode 100644
index 00000000..3154b88d
--- /dev/null
+++ b/src/PlaywrightNative.Tests/Page/PageTransition/PageTransitionTests.cs
@@ -0,0 +1,77 @@
+/*
+ * Copyright (c) 2020 Dario Kondratiuk
+ * Modifications copyright (c) Microsoft Corporation.
+ *
+ * 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
+ *
+ *     http://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.
+ */
+using System.Linq;
+using System.Threading.Tasks;
+using Microsoft.Playwright;
+using NUnit.Framework;
+using PlaywrightNative.NUnit;
+
+namespace PlaywrightNative.Tests
+{
+    /// <summary>
+    /// Official <c>page-transition.spec.ts</c>.
+    /// </summary>
+    [TestFixture]
+    public class PageTransitionTests : PageTestEx
+    {
+        [PlaywrightTest("page-transition.spec.ts", "should not crash when filter transition completes")]
+        [Test]
+        [Timeout(TestConstants.DefaultTestTimeout)]
+        public async Task ShouldNotCrashWhenFilterTransitionCompletes()
+        {
+            if (TestConstants.IsWebKit)
+            {
+                Assert.Ignore("official fixme(browserName === 'webkit'): Web process crashes on the compositor thread when a filter transitions to none");
+                return;
+            }
+
+            await using IBrowser browser = await BrowserLauncher.LaunchAsync().ConfigureAwait(false);
+            await using IBrowserContext context = await browser.NewContextAsync().ConfigureAwait(false);
+            IPage page = await context.NewPageAsync().ConfigureAwait(false);
+            await page.SetContentAsync(@"
+    <style>
+      div { transition: filter 0.1s; }
+      .dim { filter: brightness(0.95); }
+    </style>
+    " + string.Concat(Enumerable.Repeat("<div>hello</div>", 10)) + @"
+  ").ConfigureAwait(false);
+            bool crashed = false;
+            page.Crash += (_, _) => crashed = true;
+            for (int i = 0; i < 10 && !crashed; i++)
+            {
+                try
+                {
+                    await page.EvaluateAsync(@"async () => {
+      const divs = [...document.querySelectorAll('div')];
+      const settled = () => Promise.all(divs.map(div => new Promise(f => div.addEventListener('transitionend', f, { once: true }))));
+      let promise = settled();
+      divs.forEach(div => div.classList.add('dim'));
+      await promise;
+      promise = settled();
+      divs.forEach(div => div.classList.remove('dim'));
+      await promise;
+    }").ConfigureAwait(false);
+                }
+                catch (PlaywrightException)
+                {
+                }
+            }
+
+            Assert.That(crashed, Is.False);
+        }
+    }
+}
diff --git a/src/PlaywrightNative.Tests/PageNetworkResponseParityTests.cs b/src/PlaywrightNative.Tests/PageNetworkResponseParityTests.cs
index ceed21cb..238dc842 100644
--- a/src/PlaywrightNative.Tests/PageNetworkResponseParityTests.cs
+++ b/src/PlaywrightNative.Tests/PageNetworkResponseParityTests.cs
@@ -330,6 +330,29 @@ public async Task ShouldReturnUncompressedTextForBrotliEncoding()
             Assert.That(await response.TextAsync().ConfigureAwait(false), Is.EqualTo(SimpleJsonBody));
         }
 
+        [PlaywrightTest("page-network-response.spec.ts", "should return text for identity encoding")]
+        [Test]
+        [Timeout(30_000)]
+        public async Task ShouldReturnTextForIdentityEncoding()
+        {
+            EnsureServer();
+            const string text = "<div>hello</div>";
+            Server.SetRoute("/identity.html", async http =>
+            {
+                http.Response.StatusCode = 200;
+                http.Response.Headers["Content-Type"] = "text/html; charset=utf-8";
+                http.Response.Headers["Content-Encoding"] = "Identity";
+                await http.Response.WriteAsync(text).ConfigureAwait(false);
+            });
+
+            await using IBrowser browser = await BrowserLauncher.LaunchAsync().ConfigureAwait(false);
+            await using IBrowserContext context = await browser.NewContextAsync().ConfigureAwait(false);
+            IPage page = await context.NewPageAsync().ConfigureAwait(false);
+            IResponse response = await page.GoToAsync(Prefix + "/identity.html").ConfigureAwait(false);
+            Assert.That(HeaderMap.All(response.Headers)["content-encoding"], Is.EqualTo("Identity"));
+            Assert.That(await response.TextAsync().ConfigureAwait(false), Is.EqualTo(text));
+        }
+
         [PlaywrightTest("page-network-response.spec.ts", "should throw when requesting body of redirected response")]
         [Test]
         [Timeout(30_000)]
diff --git a/src/PlaywrightNative.Tests/PageScreenshotParityTests.cs b/src/PlaywrightNative.Tests/PageScreenshotParityTests.cs
index dc6235bb..58cb0dfa 100644
--- a/src/PlaywrightNative.Tests/PageScreenshotParityTests.cs
+++ b/src/PlaywrightNative.Tests/PageScreenshotParityTests.cs
@@ -20,6 +20,7 @@
 using System.Text.Json;
 using System.Threading.Tasks;
 using NUnit.Framework;
+using PlaywrightNative.Helpers;
 using PlaywrightNative.NUnit;
 using PlaywrightNative.TestServer;
 
@@ -27,9 +28,6 @@ namespace PlaywrightNative.Tests
 {
     /// <summary>
     /// Official <c>page-screenshot.spec.ts</c> titles.
-    /// Skipped (Node-only): <c>__testHookBeforeScreenshot</c>,
-    /// <c>should capture screenshots after layoutchanges in transitionend event</c>
-    /// (uses Node <c>window.builtins.Date</c>).
     /// Do not edit leftover <c>PageScreenshot*</c> /
     /// <c>ExpectScreenshot*</c>.
     /// </summary>
@@ -863,6 +861,36 @@ public async Task ShouldNotCaptureCssAnimationsInShadowDom()
             }
         }
 
+        [PlaywrightTest("page-screenshot.spec.ts", "should stop animations that happen right before screenshot")]
+        [Test]
+        [Timeout(TestConstants.DefaultTestTimeout)]
+        public async Task ShouldStopAnimationsThatHappenRightBeforeScreenshot()
+        {
+            await using IBrowser browser = await BrowserLauncher.LaunchAsync().ConfigureAwait(false);
+            await using IBrowserContext context = await browser.NewContextAsync().ConfigureAwait(false);
+            IPage page = await context.NewPageAsync().ConfigureAwait(false);
+            await page.GoToAsync(Prefix + "/rotate-z.html").ConfigureAwait(false);
+
+            // Stop rotating bar.
+            await page.EvalOnSelectorAsync("div", "el => el.style.setProperty('animation', 'none')").ConfigureAwait(false);
+            byte[] buffer1;
+
+            // Start rotating bar right before screenshot.
+            ScreenshotDecorations.TestHookBeforeScreenshot.Value = () => page.EvalOnSelectorAsync("div", "el => el.style.removeProperty('animation')");
+            try
+            {
+                buffer1 = await page.ScreenshotAsync(new() { Animations = ScreenshotAnimations.Disabled }).ConfigureAwait(false);
+            }
+            finally
+            {
+                ScreenshotDecorations.TestHookBeforeScreenshot.Value = null;
+            }
+
+            await RafRafAsync(page).ConfigureAwait(false);
+            byte[] buffer2 = await page.ScreenshotAsync(new() { Animations = ScreenshotAnimations.Disabled }).ConfigureAwait(false);
+            Assert.That(ScreenshotComparer.Matches(buffer1, buffer2, threshold: 0.2f), Is.True);
+        }
+
         [PlaywrightTest("page-screenshot.spec.ts", "should resume infinite animations")]
         [Test]
         [Timeout(TestConstants.DefaultTestTimeout)]
@@ -925,6 +953,52 @@ public async Task ShouldFireTransitionendForFiniteTransitions()
             Assert.That(await page.EvaluateAsync<bool>("() => window['__TRANSITION_END']").ConfigureAwait(false), Is.True);
         }
 
+        [PlaywrightTest("page-screenshot.spec.ts", "should capture screenshots after layoutchanges in transitionend event")]
+        [Test]
+        [Timeout(TestConstants.DefaultTestTimeout)]
+        public async Task ShouldCaptureScreenshotsAfterLayoutchangesInTransitionendEvent()
+        {
+            await using IBrowser browser = await BrowserLauncher.LaunchAsync().ConfigureAwait(false);
+            await using IBrowserContext context = await browser.NewContextAsync().ConfigureAwait(false);
+            IPage page = await context.NewPageAsync().ConfigureAwait(false);
+            await page.GoToAsync(Prefix + "/css-transition.html").ConfigureAwait(false);
+            ILocator div = page.Locator("div");
+
+            // Upstream reads the unpatched Date from window.builtins (test-only injected
+            // script); without a clock installed that is the page Date.
+            await div.EvaluateAsync<object>(@"el => {
+      el.addEventListener('transitionend', () => {
+        const builtinDate = (window.builtins && window.builtins.Date) || Date;
+        const time = builtinDate.now();
+        // Block main thread for 200ms, emulating heavy layout.
+        while (builtinDate.now() - time < 200) {}
+        const h1 = document.createElement('h1');
+        h1.textContent = 'woof-woof';
+        document.body.append(h1);
+      }, false);
+    }").ConfigureAwait(false);
+
+            // make sure transition is actually running
+            byte[] running1 = await page.ScreenshotAsync().ConfigureAwait(false);
+            await RafRafAsync(page).ConfigureAwait(false);
+            byte[] running2 = await page.ScreenshotAsync().ConfigureAwait(false);
+            Assert.That(running2, Is.Not.EqualTo(running1));
+
+            // 1. Make a screenshot that finishes all finite animations
+            //    and triggers layout.
+            byte[] screenshot1 = await page.ScreenshotAsync(new() { Animations = ScreenshotAnimations.Disabled }).ConfigureAwait(false);
+
+            // 2. Make a second screenshot after h1 is on screen.
+            await Assertions.Expect(page.Locator("h1")).ToBeVisibleAsync().ConfigureAwait(false);
+            await Assertions.Expect(page.Locator("h1")).ToHaveTextAsync("woof-woof").ConfigureAwait(false);
+            byte[] screenshot2 = await page.ScreenshotAsync().ConfigureAwait(false);
+
+            // 3. Make sure both screenshots are equal, meaning that
+            //    first screenshot actually was taken after transitionend
+            //    changed layout.
+            Assert.That(screenshot2, Is.EqualTo(screenshot1));
+        }
+
         [PlaywrightTest("page-screenshot.spec.ts", "should not change animation with playbackRate equal to 0")]
         [Test]
         [Timeout(TestConstants.DefaultTestTimeout)]
diff --git a/src/PlaywrightNative/Helpers/ScreenshotDecorations.cs b/src/PlaywrightNative/Helpers/ScreenshotDecorations.cs
index 629a3821..91b62502 100644
--- a/src/PlaywrightNative/Helpers/ScreenshotDecorations.cs
+++ b/src/PlaywrightNative/Helpers/ScreenshotDecorations.cs
@@ -175,6 +175,12 @@ internal static class ScreenshotDecorations
   style.remove();
 })()";
 
+        /// <summary>
+        /// Test-only hook (upstream <c>__testHookBeforeScreenshot</c>). Runs after the
+        /// page is prepared and right before the capture.
+        /// </summary>
+        internal static readonly AsyncLocal<Func<Task>> TestHookBeforeScreenshot = new AsyncLocal<Func<Task>>();
+
         private static readonly ConcurrentDictionary<int, SemaphoreSlim> ScreenshotGates = new ConcurrentDictionary<int, SemaphoreSlim>();
 
         /// <summary>
@@ -295,6 +301,11 @@ internal static async Task<byte[]> CaptureAsync(
                             await ScreenshotMask.ApplyAsync(page, mask, maskColor, tags).ConfigureAwait(false);
                             await WaitForFontsAsync(page).ConfigureAwait(false);
 
+                            if (TestHookBeforeScreenshot.Value != null)
+                            {
+                                await TestHookBeforeScreenshot.Value().ConfigureAwait(false);
+                            }
+
                             return await capture().ConfigureAwait(false);
                         }
                         catch (Exception ex) when (DestroyedContext.IsDestroyedContext(ex)