OffScreen - Add useLegacyRenderHandler optional param to constructor

- Defaults to true
- For those using CaptureScreenshotAsync set to false to avoid
  creating DefaultRenderHandler

CefSharp.OffScreen/ChromiumWebBrowser.cs

@@ -172,10 +172,15 @@ public bool IsBrowserInitialized
         /// this action is guranteed to be called after the browser created where as the <see cref="BrowserInitialized"/> event may be called before
         /// you have a chance to subscribe to the event as the CEF Browser is created async. (Issue https://github.com/cefsharp/CefSharp/issues/3552).
         /// </param>
+        /// <param name="useLegacyRenderHandler">
+        /// For those using <see cref="ScreenshotAsync(bool, PopupBlending)"/> or <see cref="ScreenshotOrNull(PopupBlending)"/> then
+        /// this must be true, for those using <see cref="CaptureScreenshotAsync(CaptureScreenshotFormat?, int?, Viewport)"/> this can be false.
+        /// Lower memory usage when false. Defaults to true for backwards compatability.
+        /// </param>
         /// <exception cref="System.InvalidOperationException">Cef::Initialize() failed</exception>
         public ChromiumWebBrowser(HtmlString html, IBrowserSettings browserSettings = null,
             IRequestContext requestContext = null, bool automaticallyCreateBrowser = true,
-            Action<IBrowser> onAfterBrowserCreated = null) : this(html.ToDataUriString(), browserSettings, requestContext, automaticallyCreateBrowser, onAfterBrowserCreated)
+            Action<IBrowser> onAfterBrowserCreated = null, bool useLegacyRenderHandler = true) : this(html.ToDataUriString(), browserSettings, requestContext, automaticallyCreateBrowser, onAfterBrowserCreated, useLegacyRenderHandler)
         {
         }
 
@@ -195,10 +200,15 @@ public ChromiumWebBrowser(HtmlString html, IBrowserSettings browserSettings = nu
         /// this action is guranteed to be called after the browser created where as the <see cref="BrowserInitialized"/> event may be called before
         /// you have a chance to subscribe to the event as the CEF Browser is created async. (Issue https://github.com/cefsharp/CefSharp/issues/3552).
         /// </param>
+        /// <param name="useLegacyRenderHandler">
+        /// For those using <see cref="ScreenshotAsync(bool, PopupBlending)"/> or <see cref="ScreenshotOrNull(PopupBlending)"/> then
+        /// this must be true, for those using <see cref="CaptureScreenshotAsync(CaptureScreenshotFormat?, int?, Viewport)"/> this can be false.
+        /// Lower memory usage when false. Defaults to true for backwards compatability.
+        /// </param>
         /// <exception cref="System.InvalidOperationException">Cef::Initialize() failed</exception>
         public ChromiumWebBrowser(string address = "", IBrowserSettings browserSettings = null,
             IRequestContext requestContext = null, bool automaticallyCreateBrowser = true,
-            Action<IBrowser> onAfterBrowserCreated = null)
+            Action<IBrowser> onAfterBrowserCreated = null, bool useLegacyRenderHandler = true)
         {
             if (!Cef.IsInitialized)
             {
@@ -223,7 +233,10 @@ public ChromiumWebBrowser(string address = "", IBrowserSettings browserSettings
                 CreateBrowser(null, browserSettings);
             }
 
-            RenderHandler = new DefaultRenderHandler(this);
+            if (useLegacyRenderHandler)
+            {
+                RenderHandler = new DefaultRenderHandler(this);
+            }
         }
 
         /// <summary>

CefSharp.Test/ChromiumWebBrowserOffScreenFixture.cs

@@ -22,7 +22,7 @@ Task IAsyncLifetime.DisposeAsync()
 
         Task IAsyncLifetime.InitializeAsync()
         {
-            Browser = new ChromiumWebBrowser(CefExample.HelloWorldUrl);
+            Browser = new ChromiumWebBrowser(CefExample.HelloWorldUrl, useLegacyRenderHandler: false);
 
             return Browser.WaitForInitialLoadAsync();
         }

CefSharp.Test/DevTools/DevToolsClientFacts.cs

@@ -35,7 +35,7 @@ public DevToolsClientFacts(ITestOutputHelper output, CefSharpFixture fixture)
         [Fact]
         public async Task CanCaptureScreenshot()
         {
-            using (var browser = new ChromiumWebBrowser("www.google.com"))
+            using (var browser = new ChromiumWebBrowser("www.google.com", useLegacyRenderHandler: false))
             {
                 await browser.WaitForInitialLoadAsync();
 
@@ -81,7 +81,7 @@ public void CanConvertDevToolsObjectToDictionary()
         [Fact]
         public async Task CanGetDevToolsProtocolVersion()
         {
-            using (var browser = new ChromiumWebBrowser("www.google.com"))
+            using (var browser = new ChromiumWebBrowser("www.google.com", useLegacyRenderHandler: false))
             {
                 await browser.WaitForInitialLoadAsync();
 
@@ -102,7 +102,7 @@ public async Task CanGetDevToolsProtocolVersion()
         [Fact]
         public async Task CanEmulationCanEmulate()
         {
-            using (var browser = new ChromiumWebBrowser("www.google.com"))
+            using (var browser = new ChromiumWebBrowser("www.google.com", useLegacyRenderHandler: false))
             {
                 await browser.WaitForInitialLoadAsync();
 
@@ -118,7 +118,7 @@ public async Task CanEmulationCanEmulate()
         [Fact]
         public async Task CanGetPageNavigationHistory()
         {
-            using (var browser = new ChromiumWebBrowser("www.google.com"))
+            using (var browser = new ChromiumWebBrowser("www.google.com", useLegacyRenderHandler: false))
             {
                 await browser.WaitForInitialLoadAsync();
 
@@ -141,7 +141,7 @@ public async Task CanGetPageNavigationHistory()
         [InlineData("CefSharpTest1", "CefSharp Test Cookie2", CefExample.ExampleDomain, CookieSameSite.Lax)]
         public async Task CanSetCookieForDomain(string name, string value, string domain, CookieSameSite sameSite)
         {
-            using (var browser = new ChromiumWebBrowser("www.google.com"))
+            using (var browser = new ChromiumWebBrowser("www.google.com", useLegacyRenderHandler: false))
             {
                 await browser.WaitForInitialLoadAsync();
 
@@ -157,7 +157,7 @@ public async Task CanSetCookieForDomain(string name, string value, string domain
         [Fact]
         public async Task CanUseMultipleDevToolsClientInstancesPerBrowser()
         {
-            using (var browser = new ChromiumWebBrowser("www.google.com"))
+            using (var browser = new ChromiumWebBrowser("www.google.com", useLegacyRenderHandler: false))
             {
                 await browser.WaitForInitialLoadAsync();
 
@@ -190,7 +190,7 @@ public async Task CanUseMultipleDevToolsClientInstancesPerBrowser()
         [Fact]
         public async Task CanSetUserAgentOverride()
         {
-            using (var browser = new ChromiumWebBrowser("www.google.com"))
+            using (var browser = new ChromiumWebBrowser("www.google.com", useLegacyRenderHandler: false))
             {
                 await browser.WaitForInitialLoadAsync();
 
@@ -259,7 +259,7 @@ public async Task CanSetUserAgentOverride()
         [Fact]
         public async Task CanSetExtraHTTPHeaders()
         {
-            using (var browser = new ChromiumWebBrowser("about:blank", automaticallyCreateBrowser: false))
+            using (var browser = new ChromiumWebBrowser("about:blank", automaticallyCreateBrowser: false, useLegacyRenderHandler: false))
             {
                 await browser.CreateBrowserAsync();
 
@@ -307,7 +307,7 @@ public async Task CanSetExtraHTTPHeaders()
         [Fact]
         public async Task ExecuteDevToolsMethodThrowsExceptionWithInvalidMethod()
         {
-            using (var browser = new ChromiumWebBrowser("www.google.com"))
+            using (var browser = new ChromiumWebBrowser("www.google.com", useLegacyRenderHandler: false))
             {
                 await browser.WaitForInitialLoadAsync();
 
@@ -327,7 +327,7 @@ public async Task ExecuteDevToolsMethodThrowsExceptionWithInvalidMethod()
         [Fact]
         public async Task CanGetMediaQueries()
         {
-            using (var browser = new ChromiumWebBrowser("https://cefsharp.github.io/demo/mediaqueryhover.html"))
+            using (var browser = new ChromiumWebBrowser("https://cefsharp.github.io/demo/mediaqueryhover.html", useLegacyRenderHandler: false))
             {
                 await browser.WaitForInitialLoadAsync();
 
@@ -346,7 +346,7 @@ public async Task CanGetMediaQueries()
         [Fact]
         public async Task CanRegisterMultipleEventHandlers()
         {
-            using (var browser = new ChromiumWebBrowser("about:blank", automaticallyCreateBrowser: false))
+            using (var browser = new ChromiumWebBrowser("about:blank", automaticallyCreateBrowser: false, useLegacyRenderHandler: false))
             {
                 await browser.CreateBrowserAsync();
 

CefSharp.Test/Javascript/EvaluateScriptAsPromiseAsyncFacts.cs

@@ -33,7 +33,7 @@ public EvaluateScriptAsPromiseAsyncFacts(ITestOutputHelper output, CefSharpFixtu
         [InlineData("var result = await fetch('./robots.txt'); return result.status;", true, "200")]
         public async Task CanEvaluateScriptAsPromiseAsync(string script, bool success, string expected)
         {
-            using (var browser = new ChromiumWebBrowser("http://www.google.com"))
+            using (var browser = new ChromiumWebBrowser("http://www.google.com", useLegacyRenderHandler: false))
             {
                 var response = await browser.WaitForInitialLoadAsync();
 
@@ -66,7 +66,7 @@ public async Task CanEvaluateScriptAsPromiseAsync(string script, bool success, s
         [InlineData("function sleep(ms) { return new Promise(resolve => setTimeout(resolve, ms)); }; async function getValAfterSleep() { await sleep(1000); return { a: 'CefSharp', b: 42 }; }; await sleep(2000); const result = await getValAfterSleep(); await sleep(2000); return result;", true, "CefSharp", "42")]
         public async Task CanEvaluateScriptAsPromiseAsyncReturnObject(string script, bool success, string expectedA, string expectedB)
         {
-            using (var browser = new ChromiumWebBrowser("http://www.google.com"))
+            using (var browser = new ChromiumWebBrowser("http://www.google.com", useLegacyRenderHandler: false))
             {
                 var response = await browser.WaitForInitialLoadAsync();
 

CefSharp.Test/Navigation/WaitForNavigationAsyncTests.cs

@@ -28,7 +28,7 @@ public async Task CanWork()
         {
             const string expected = CefExample.HelloWorldUrl;
 
-            using (var browser = new ChromiumWebBrowser(CefExample.DefaultUrl))
+            using (var browser = new ChromiumWebBrowser(CefExample.DefaultUrl, useLegacyRenderHandler: false))
             {
                 var response = await browser.WaitForInitialLoadAsync();
 
@@ -54,7 +54,7 @@ public async Task CanWork()
         public async Task CanWaitForInvalidDomain()
         {
             const string expected = "https://notfound.cefsharp.test";
-            using (var browser = new ChromiumWebBrowser(CefExample.DefaultUrl))
+            using (var browser = new ChromiumWebBrowser(CefExample.DefaultUrl, useLegacyRenderHandler: false))
             {
                 var response = await browser.WaitForInitialLoadAsync();
 
@@ -82,7 +82,7 @@ public async Task CanTimeout()
         {
             const string expected = "The operation has timed out.";
 
-            using (var browser = new ChromiumWebBrowser(CefExample.DefaultUrl))
+            using (var browser = new ChromiumWebBrowser(CefExample.DefaultUrl, useLegacyRenderHandler: false))
             {
                 var response = await browser.WaitForInitialLoadAsync();
 
@@ -104,7 +104,7 @@ public async Task CanCancel()
         {
             const string expected = "A task was canceled.";
 
-            using (var browser = new ChromiumWebBrowser(CefExample.DefaultUrl))
+            using (var browser = new ChromiumWebBrowser(CefExample.DefaultUrl, useLegacyRenderHandler: false))
             {
                 var response = await browser.WaitForInitialLoadAsync();