### Install Visual Studio components

Source: https://github.com/chromiumembedded/cef/blob/master/docs/automated_build_setup.md

Use these arguments with the Visual Studio installer to set up the required native desktop and ATL/MFC components.

```sh
$ PATH_TO_INSTALLER.EXE ^
--add Microsoft.VisualStudio.Workload.NativeDesktop ^
--add Microsoft.VisualStudio.Component.VC.ATLMFC ^
--includeRecommended
```

```sh
$ PATH_TO_INSTALLER.EXE ^
--add Microsoft.VisualStudio.Component.VC.Tools.ARM64 ^
--add Microsoft.VisualStudio.Component.VC.MFC.ARM64 ^
--includeRecommended
```

--------------------------------

### JavaScript: Initialize Server Setup

Source: https://github.com/chromiumembedded/cef/blob/master/tests/cefclient/resources/server.html

Performs initial setup by querying the server state and updating button states and port input. This function should only be run from the 'https://tests' origin.

```javascript
function setup() {
  if (location.origin != 'https://tests') {
    document.getElementById('warning').style.display = 'block';
    return;
  }
  // Query the current server state.
  sendMessage({'action':'query'}, function(response) {
    if (response['result'] == 'success') {
      var running = (response['status'] == 'running')
      setButtonState(!running, running);
      var port_element = document.getElementById('port');
      port_element.value = response['port'];
      port_element.disabled = false;
    }
  });
}
```

--------------------------------

### Initial Setup and Interval Timer

Source: https://github.com/chromiumembedded/cef/blob/master/tests/cefclient/resources/hang.html

Sets up the initial state of the test page by disabling form elements, updating the time, and starting an interval timer to refresh the time every second. It also conditionally calls `setupTest` if the page is loaded from 'tests' or 'localhost'.

```JavaScript
function setup() {
  // Disable all elements.
  setFormEnabled(false);
  updateTime();
  setInterval(updateTime, 1000);
  if (location.hostname == 'tests' || location.hostname == 'localhost') {
    setupTest();
    return;
  }
  alert('This page can only be run from tests or localhost.');
}
```

--------------------------------

### Install websocket-client

Source: https://github.com/chromiumembedded/cef/blob/master/tools/debug/ax_viewport_collapse/README.md

Install the necessary Python package for websocket communication.

```bash
python3 -m pip install websocket-client
```

--------------------------------

### Example Directory Structure

Source: https://github.com/chromiumembedded/cef/blob/master/docs/using_chrome_driver.md

Expected file layout for the automation project.

```text
c:\temp\
  cef_binary_3.2171.1979_windows32_client\
    Release\
      cefclient.exe  (and other files)
  chromedriver.exe
  Example.java
  selenium-server-standalone-2.44.0.jar
```

--------------------------------

### Setup VSCode Environment

Source: https://github.com/chromiumembedded/cef/blob/master/docs/master_build_quick_start.md

Initialize the preconfigured VSCode environment for CEF development.

```sh
cd /path/to/code/chromium_git/chromium/src/cef
python3 tools/setup_vscode.py
```

--------------------------------

### Example Verification Command

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLAUDE_PATCH_INSTRUCTIONS.md

An example of the verify_patch.py command with specific parameters for patch name and version numbers.

```bash
# From chromium/src/cef/tools/claude directory:
python3 verify_patch.py patch_output.txt --patch views_widget \
  --old-version 142.0.7444.0 --new-version 143.0.7491.0
```

--------------------------------

### Prepare Sync Directories

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLAUDE_BASE_SYNC_INSTRUCTIONS.md

Initialize the necessary working directories and capture current repository state before starting the sync process.

```bash
# Create working directories
mkdir -p cef/tmp/backup
mkdir -p cef/tmp/diffs

# Note the current Chromium commit
git log -1 --format='%H' HEAD
cat chrome/VERSION
```

--------------------------------

### WebSocket Client Setup and Connection Logic

Source: https://github.com/chromiumembedded/cef/blob/master/tests/cefclient/resources/websocket.html

This JavaScript code handles the initial setup of the WebSocket client, including determining the server URL and managing the connection state. It's designed to be run in a browser environment.

```javascript
var ws = null;
function setup() {
    // Match the secure state of the current origin.
    var origin = location.origin;
    if (origin.indexOf('http://') == 0) {
        origin = origin.replace('http://', 'ws://');
    } else if (origin.indexOf('https://') == 0) {
        origin = origin.replace('https://', 'wss://');
    } else {
        origin = '';
    }
    if (origin.length > 0)
        document.getElementById('server').value = origin;
    document.getElementById('server').disabled = false;
    if (location.hostname != 'localhost')
        document.getElementById('warning').style.display = 'block';
    setConnected(false);
}
function setConnected(connected) {
    document.getElementById('connect').disabled = connected;
    document.getElementById('disconnect').disabled = !connected;
    document.getElementById('message').disabled = !connected;
    document.getElementById('response').disabled = !connected;
    document.getElementById('send').disabled = !connected;
}
function doConnect() {
    var url = document.getElementById('server').value;
    if (url.indexOf('ws://') < 0 && url.indexOf('wss://') < 0) {
        alert('Specify a valid WebSocket server URL.');
        return;
    }
    if (ws)
    {
        alert('WebSocket is already connected.');
        return;
    }
    ws = new WebSocket(url);
    ws.onopen = function() {
        setConnected(true);
    };
    ws.onmessage = function(event) {
        document.getElementById('response').value = event.data;
    };
    ws.onclose = function(event) {
        setConnected(false);
        ws = null;
    };
    ws.onerror = function(event) {
        if (ws.readyState == 3)
            alert('WebSocket connection failed.');
    }
}
function doDisconnect() {
    if (!ws)
    {
        alert('WebSocket is not currently connected.');
        return;
    }
    ws.close();
}
function doSend() {
    if (!ws)
    {
        alert('WebSocket is not currently connected.');
        return;
    }
    var value = document.getElementById('message').value;
    if (value.length > 0)
        ws.send(value);
}
```

--------------------------------

### cef-project Examples

Source: https://github.com/chromiumembedded/cef/blob/master/docs/hands_on_tutorial.md

Discover focused example applications within the cef-project repository that demonstrate specific CEF features like message routing, resource management, and custom scheme handlers.

```url
https://github.com/chromiumembedded/cef-project
```

--------------------------------

### Launch VSCode

Source: https://github.com/chromiumembedded/cef/blob/master/docs/master_build_quick_start.md

Open the current directory in VSCode after the environment setup is complete.

```sh
cd /path/to/code/chromium_git/chromium/src
code .
```

--------------------------------

### Install and Update depot_tools

Source: https://github.com/chromiumembedded/cef/blob/master/docs/master_build_quick_start.md

Navigate to the depot_tools directory and run the update script to install Python and Git. This script also handles auto-updating depot_tools.

```bash
cd c:\code\depot_tools
update_depot_tools.bat
```

--------------------------------

### Configure Tool Arguments

Source: https://github.com/chromiumembedded/cef/blob/master/tools/clang/README.md

Examples of passing specific transformation flags to the rewriter.

```bash
# Run only iterator-loops transformation
--tool-args="--only=iterator-loops"

# Run only contains and structured-bindings
--tool-args="--only=contains,structured-bindings"

# Disable specific transformation (all others still run)
--tool-args="--contains=false"
```

--------------------------------

### Install Build Dependencies

Source: https://github.com/chromiumembedded/cef/blob/master/docs/master_build_quick_start.md

Installs required build dependencies using apt-get and a Python script. Ensure you answer 'Y' to all prompts during the script execution. This step is crucial for a successful build.

```sh
cd ~/code
sudo apt-get install curl file lsb-release procps python3 python3-pip
curl 'https://chromium.googlesource.com/chromium/src/+/main/build/install-build-deps.py?format=TEXT' | base64 -d > install-build-deps.py
sudo python3 ./install-build-deps.py --no-arm --no-chromeos-fonts --no-nacl
python3 -m pip install dataclasses importlib_metadata
```

--------------------------------

### Full Cherry-Pick Workflow Example

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLAUDE_CHERRY_PICK_INSTRUCTIONS.md

Demonstrates a complete workflow for cherry-picking a commit, including fetching, applying, extracting, and resaving patches.

```bash
# Setup
cd /path/to/chromium/src/cef
git fetch upstream master

# Cherry-pick commit that modifies views_widget.patch
git cherry-pick abc123 --no-commit

# Check what source file changes are needed
git diff abc123^..abc123 -- patch/patches/views_widget.patch

# Extract and apply the source changes
git show abc123:patch/patches/views_widget.patch > /tmp/vw.patch
sed -n '/^diff --git ui/views/widget/widget.cc/,/^diff --git /p' /tmp/vw.patch | head -n -1 > /tmp/widget.patch
cd /path/to/chromium/src
patch -p0 < /tmp/widget.patch

# Resave and commit
cd cef
python3 tools/patch_updater.py --resave --patch views_widget
git add patch/patches/views_widget.patch
git commit -m "$(git log -1 --format='%B' abc123)"
```

--------------------------------

### Example crash_reporter.cfg file contents

Source: https://github.com/chromiumembedded/cef/blob/master/docs/crash_reporting.md

A sample configuration file demonstrating the [Config] and [CrashKeys] sections for enabling crash reporting.

```ini
[Config]
# Product information.
ProductName=cefclient
ProductVersion=1.0.0

# Required to enable crash dump upload.
ServerURL=http://localhost:8080

# Disable rate limiting so that all crashes are uploaded.
RateLimitEnabled=false
MaxUploadsPerDay=0

[CrashKeys]
```

--------------------------------

### JavaScript Setup Function

Source: https://github.com/chromiumembedded/cef/blob/master/tests/cefclient/resources/window.html

Initializes the page by disabling form elements if not running on 'tests' or 'localhost'.

```javascript
function setup() {
  if (location.hostname == 'tests' || location.hostname == 'localhost') return;
  alert('This page can only be run from tests or localhost.');
  // Disable all elements.
  var elements = document.getElementById("form").elements;
  for (var i = 0, element; element = elements[i++]; ) {
    element.disabled = true;
  }
}
```

--------------------------------

### Prompt for Custom Scheme Handler

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLIENT_DEVELOPMENT.md

Example prompt for implementing a custom protocol handler.

```text
I have a CEF binary distribution at /path/to/cef_binary_<version>_<platform>.

Please add support for a custom "myscheme://" protocol to cefsimple that
serves static HTML pages from an in-memory map.

Use @cef/tools/claude/CLAUDE_CLIENT_INSTRUCTIONS.md for guidance.
```

--------------------------------

### Bootstrap Clang Rewriter

Source: https://github.com/chromiumembedded/cef/blob/master/tools/clang/README.md

Initial one-time setup to build the clang rewriter tool.

```bash
# From chromium/src directory
./cef/tools/clang/scripts/build_clang_rewriter.sh
```

--------------------------------

### Build cefclient with Bazel

Source: https://github.com/chromiumembedded/cef/blob/master/tools/distrib/mac/README.standard.txt

Use this command to build the bundled cefclient sample application using Bazel. Ensure Bazelisk is installed.

```bash
bazel build //tests/cefclient
```

--------------------------------

### Remote Configuration Output

Source: https://github.com/chromiumembedded/cef/blob/master/docs/contributing_with_git.md

Example output showing the expected configuration of origin, public, and upstream remotes.

```cpp
origin    https://<UserName>@github.com/<UserName>/cef_private.git (fetch)
origin    https://<UserName>@github.com/<UserName>/cef_private.git (push)
public    https://<UserName>@github.com/<UserName>/cef.git (fetch)
public    https://<UserName>@github.com/<UserName>/cef.git (push)
upstream    https://github.com/chromiumembedded/cef.git (fetch)
upstream    https://github.com/chromiumembedded/cef.git (push)
```

--------------------------------

### Prompt for Customizing Popup Windows

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLIENT_DEVELOPMENT.md

Example prompt for setting a specific size for popup windows.

```text
I have a CEF binary distribution at /path/to/cef_binary_<version>_windows64.

Please make cefsimple popup windows open at 600x400 instead of the default size.

Follow the instructions in @cef/tools/claude/CLAUDE_CLIENT_INSTRUCTIONS.md
```

--------------------------------

### Run cefclient with Bazel

Source: https://github.com/chromiumembedded/cef/blob/master/tools/distrib/mac/README.standard.txt

Use this command to run the bundled cefclient sample application using Bazel. Ensure Bazelisk is installed.

```bash
bazel run //tests/cefclient
```

--------------------------------

### Image Transparency Example

Source: https://github.com/chromiumembedded/cef/blob/master/tests/cefclient/resources/transparency.html

Demonstrates how to make an image fully opaque on hover using CSS opacity. No specific setup is required beyond including the CSS.

```css
body {
  font-family: Verdana, Arial;
}
img {
  opacity:0.4;
}
img:hover {
  opacity:1.0;
}
```

--------------------------------

### Incremental Prompting for Chromium Updates

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/README.md

Guide Claude Code through large tasks like Chromium updates by using incremental prompts. Start with one instruction file, allow Claude to work, and then provide the next step.

```text
1. "Start fixing patches using @CLAUDE_PATCH_INSTRUCTIONS.md"
2. [Claude works for a while]
3. "Good progress. Continue with the remaining patches."
4. [Claude finishes]
5. "Now let's fix build errors using @CLAUDE_BUILD_INSTRUCTIONS.md"
```

--------------------------------

### Main Function Setup - C

Source: https://github.com/chromiumembedded/cef/blob/master/docs/using_the_capi.md

Initializes CEF and sets up the main application structure. This function configures the API version, handles main arguments, and prepares the application for execution.

```c
// Complete main() function (Windows/Linux pattern)
// NOTE: On macOS, you must call cef_load_library() first, then cef_api_hash().
// See cefsimple_capi/cefsimple_mac.m for the macOS implementation.
int main(int argc, char* argv[]) {
  // Configure the CEF API version. This must be called before any other CEF
  // API functions.
  cef_api_hash(CEF_API_VERSION, 0);

  cef_main_args_t main_args = {};
#ifdef _WIN32
  main_args.instance = GetModuleHandle(NULL);
#else
  main_args.argc = argc;
  main_args.argv = argv;
#endif

  // Create app with browser process handler (with 1 reference)
  my_app_complete_t* app = create_app_complete();

  // Add a reference before cef_execute_process. Both cef_execute_process and
  // cef_initialize will take ownership of a reference, so we need 2 total.
  app->app.base.add_ref(&app->app.base);

  // Execute sub-processes if needed

```

--------------------------------

### JavaScript: Start Server

Source: https://github.com/chromiumembedded/cef/blob/master/tests/cefclient/resources/server.html

Starts the server with a specified port number. Validates the port to be between 1025 and 65535. Updates button states based on the start operation's success or failure.

```javascript
function startServer() {
  var port = parseInt(document.getElementById('port').value);
  if (port < 1025 || port > 65535) {
    alert('Specify a port number between 1025 and 65535');
    return;
  }
  setButtonState(false, false);
  sendMessage({'action':'start', 'port':port}, function(response) {
    if (response['result'] == 'success') {
      setButtonState(false, true);
    } else {
      setButtonState(true, false);
      alert(response['message']);
    }
  });
}
```

--------------------------------

### Run sample applications

Source: https://github.com/chromiumembedded/cef/blob/master/docs/master_build_quick_start.md

Launch the compiled sample applications from the build output directory.

```sh
cd ~/code/chromium_git/chromium/src
open out/Debug_GN_x64/cefclient.app
# Or run directly in the console to see log output:
./out/Debug_GN_x64/cefclient.app/Contents/MacOS/cefclient
```

--------------------------------

### Install Python 3.12 on macOS

Source: https://github.com/chromiumembedded/cef/blob/master/tools/clang/README.md

Commands to install the required Python version via Homebrew and update the shell path.

```bash
brew install python@3.12
ln -s /opt/homebrew/opt/python@3.12/bin/python3.12 /opt/homebrew/opt/python@3.12/bin/python3
export PATH="/opt/homebrew/opt/python@3.12/bin:$PATH"
python3 --version  # Should show 3.12.x
```

--------------------------------

### Setup Test Environment

Source: https://github.com/chromiumembedded/cef/blob/master/tests/cefclient/resources/hang.html

Initializes the test environment by retrieving the currently configured command and enabling form elements. It uses `window.cefQuery` to communicate with the browser process.

```JavaScript
function setupTest() {
  // Retrieve the currently configured command.
  // Results in a call to the OnQuery method in hang_test.cc
  window.cefQuery({
    request: 'HangTest:getcommand',
    onSuccess: function(response) {
      document.getElementById(response).checked = true;
      setFormEnabled(true);
    },
  });
}
```

--------------------------------

### Build and Run CEF Sample Applications

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLAUDE_BASE_SYNC_INSTRUCTIONS.md

Compile the 'cefsimple' and 'cefclient' sample applications. After compilation, run these applications to test CEF integration.

```bash
autoninja -C out/Debug_GN_x64 cefsimple cefclient
out/Debug_GN_x64/cefsimple
out/Debug_GN_x64/cefclient
```

--------------------------------

### CEF Crash Report Console Output Example

Source: https://github.com/chromiumembedded/cef/blob/master/docs/crash_reporting.md

This is an example of the console output observed when a crash report is successfully received and processed by CEF.

```text
01/10/2017 12:31:23: Dump <id>
```

--------------------------------

### C++ Reference Counting Example

Source: https://github.com/chromiumembedded/cef/blob/master/docs/using_the_capi.md

This C++ example demonstrates how reference counting is typically handled for classes inheriting from CefApp and CefBrowserProcessHandler, serving as a comparison to C API structure management.

```cpp
// A new class is defined and specific handlers are overridden
class SimpleApp: public CefApp, public CefBrowserProcessHandler {
  public:
    SimpleApp() {}

    CefRefPtr<CefBrowserProcessHandler> GetBrowserProcessHandler() override {
      return this;
    }

    void OnContextInitialized() override;
    CefRefPtr<CefClient> GetDefaultClient() override;

 private:
  // A default RC implementation can be used
  IMPLEMENT_REFCOUNTING(SimpleApp);
}
```

--------------------------------

### Page Setup and Hostname Check

Source: https://github.com/chromiumembedded/cef/blob/master/tests/cefclient/resources/dialogs.html

Initializes the page by updating the time and setting up an interval for time updates. It also checks if the page is running on 'tests' or 'localhost' and alerts the user otherwise.

```javascript
function setup() {
  update_time();
  setInterval(update_time, 1000);
  if (location.hostname != 'tests' && location.hostname != 'localhost') {
    alert('Parts of this page can only be run from tests or localhost.');
    return;
  }
  // Enable all elements.
  var elements = document.getElementById("form").elements;
  for (var i = 0, element; element = elements[i++]; ) {
    element.disabled = false;
  }
}

window.addEventListener('load', setup, false);
```

--------------------------------

### Browser Process Crash Metadata Example (JSON)

Source: https://github.com/chromiumembedded/cef/blob/master/docs/crash_reporting.md

Example JSON structure of metadata collected for a browser process crash, including system information, command-line switches, and custom crash keys.

```json
{
  "LOG_FATAL": "debug_urls.cc:208: Check failed: false. \n0   Chromium Embedded Framework         0x00000001161a1a0e _ZN4base5debug10StackTraceC2Ev + 30\n1   Chromium Embedded Framework         0x00000001161a1a75 _ZN4base5debug10StackTraceC1Ev + 21\n2   Chromium Embedded Fr",
  "guid": "6ada20da-7306-477e-a715-ada36448a23f",
  "num-switches": "3",
  "pid": "2073",
  "platform": "macos",
  "product": "cefclient",
  "ptype": "browser",
  "switch-1": "--url=chrome://inducebrowsercrashforrealz",
  "switch-2": "--lang=en-US",
  "testkey_large1": "value1_large_browser", 
  "testkey_large2": "value2_large_browser", 
  "testkey_medium1": "value1_medium_browser", 
  "testkey_medium2": "value2_medium_browser", 
  "testkey_small1": "value1_small_browser", 
  "testkey_small2": "value2_small_browser", 
  "version": "1.0.0"
}
```

--------------------------------

### Starting Build Error Fixing with Raw Output

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CHROMIUM_UPDATE.md

Use this prompt structure when providing raw build output, ensuring the analysis script is run first.

```text
Please fix build errors for the 139.0.7258.0 to 140.0.7339.0 update
using the instructions in @cef/tools/claude/CLAUDE_BUILD_INSTRUCTIONS.md

Raw build output: @cef/tools/claude/build_output.txt
Target: cef
Out dir: Debug_GN_x64

Please run analyze_build_output.py first to understand what failed.
```

--------------------------------

### Example Compile Error

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLAUDE_BUILD_INSTRUCTIONS.md

Illustrates a common compile error where a struct member is missing. This example shows the file, line number, column, error message, and the specific line of code causing the issue.

```cpp
cef/libcef/browser/browser_host_impl.cc:123:45: error: 'CreateParams' has no member named 'initial_size'
    params.initial_size = gfx::Size(800, 600);
                          ^

```

--------------------------------

### Run CEF Simple with Local or Data URLs

Source: https://github.com/chromiumembedded/cef/blob/master/docs/hands_on_tutorial.md

Examples for loading local files or inline data URLs via command line.

```bash
cefsimple --url=file:///home/user/test.html
```

```bash
cefsimple --url="data:text/html,<h1>Hello!</h1>"
```

--------------------------------

### Build and run CEF sample applications with Bazel

Source: https://github.com/chromiumembedded/cef/blob/master/tools/distrib/linux/README.standard.txt

Commands to compile and execute the cefclient sample application.

```bash
$ bazel build //tests/cefclient
```

```bash
$ bazel run //tests/cefclient
```

--------------------------------

### C API Manual Reference Counting Example

Source: https://github.com/chromiumembedded/cef/blob/master/docs/using_the_capi.md

Illustrates manual reference counting in the CEF C API, mirroring the C++ CefRefPtr behavior. This example requires explicit calls to release objects when they are no longer needed.

```c
void use_frame_in_c(cef_browser_t* browser) {
  // browser parameter: CEF already added a reference before calling us

  cef_frame_t* frame = browser->get_main_frame(browser);
  // frame: get_main_frame() returns a pointer with a reference

  cef_string_t url = {};
  cef_string_from_ascii("https://example.com", 19, &url);
  frame->load_url(frame, &url);
  cef_string_clear(&url);

  // Exiting function - MUST manually release:
  frame->base.release(&frame->base);    // Manual (CefRefPtr does automatically)
  browser->base.release(&browser->base); // Manual (CefRefPtr does automatically)
}
```

--------------------------------

### Create Linux/Mac Build Configuration Helper

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CHROMIUM_UPDATE.md

Create this script on Linux/Mac to simplify regenerating build files after .gn changes. Ensure to replace the placeholder with your platform's build config.

```bash
#!/bin/bash
export GN_OUT_CONFIGS=Debug_GN_arm64
./cef_create_projects.sh
```

--------------------------------

### Build cefsimple on Linux

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLAUDE_CLIENT_INSTRUCTIONS.md

Commands to configure and build the test application on Linux.

```bash
cmake -B build
cmake --build build --target cefsimple
build/tests/cefsimple/cefsimple
```

--------------------------------

### Run CEF Sample Browser

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLAUDE_SRC_PATCH_INSTRUCTIONS.md

Launch the CEF sample browser application to manually test the changes and verify the patch works as intended.

```bash
# Or test manually with the sample browser
out/Debug_GN_x64/cefclient
```

--------------------------------

### Get Full Commit Message

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLAUDE_CHERRY_PICK_INSTRUCTIONS.md

Retrieves the complete commit message for a given SHA.

```git
git log -1 --format='%B' <sha>
```

--------------------------------

### Build cefsimple on Windows

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLAUDE_CLIENT_INSTRUCTIONS.md

Commands to configure and build the test application using Visual Studio.

```bash
cmake -B build -G "Visual Studio 17 2022" -A x64 -DUSE_SANDBOX=OFF
cmake --build build --config Release --target cefsimple
build\tests\cefsimple\Release\cefsimple.exe
```

--------------------------------

### Get Patch File from Commit

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLAUDE_CHERRY_PICK_INSTRUCTIONS.md

Retrieves the patch file associated with a specific commit.

```git
git show <sha>:patch/patches/<name>.patch
```

--------------------------------

### Install patchelf dependency for Bazel

Source: https://github.com/chromiumembedded/cef/blob/master/tools/distrib/linux/README.standard.txt

Required system package for building CEF with Bazel on Linux.

```bash
$ sudo apt install patchelf
```

--------------------------------

### Run Initial CEF Build

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLAUDE_BUILD_INSTRUCTIONS.md

Execute this command from the chromium/src directory to perform an initial build and capture all output. The -k 0 flag ensures the build continues on errors, allowing all failures to be collected. Redirect output to a file for analysis.

```bash
autoninja -k 0 -C out/Debug_GN_x64 cef 2>&1 | tee cef/tools/claude/build_output.txt
```

--------------------------------

### Prompt for Intercepting Network Requests

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLIENT_DEVELOPMENT.md

Example prompt for logging image request URLs to the console.

```text
I have a CEF binary distribution at /path/to/cef_binary_<version>_linux64.

Please modify cefsimple to intercept all image requests and log their URLs to
the console.

Use @cef/tools/claude/CLAUDE_CLIENT_INSTRUCTIONS.md for guidance.
```

--------------------------------

### Run cefclient Sample Application

Source: https://github.com/chromiumembedded/cef/blob/master/docs/chromium_update.md

Command-line arguments for testing various runtime modes of the cefclient application.

```sh
# Chrome bootstrap: 
$ cefclient 

# Chrome bootstrap + Alloy style: 
$ cefclient --use-alloy-style 
$ cefclient --use-alloy-style --use-native 
$ cefclient --off-screen-rendering-enabled 

# Multi-threaded message loop (Windows/Linux only): 
$ cefclient --multi-threaded-message-loop 
$ cefclient --use-alloy-style --multi-threaded-message-loop 

# Chrome style + native parent (Windows/Linux only): 
$ cefclient --use-native
```

--------------------------------

### Prompt for JavaScript-to-C++ Communication

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLIENT_DEVELOPMENT.md

Example prompt for adding a JS function that sends messages to C++.

```text
I have a CEF binary distribution at /path/to/cef_binary_<version>_macosarm64.

Please add a JavaScript function window.sendToApp(message) to cefsimple that
sends messages to C++ and displays them via LOG().

Use @cef/tools/claude/CLAUDE_CLIENT_INSTRUCTIONS.md for guidance.
```

--------------------------------

### Prompt for Custom URL Scheme

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLIENT_DEVELOPMENT.md

Example prompt for adding a custom URL scheme to cefsimple.

```text
I have a CEF binary distribution at /path/to/cef_binary_<version>_<platform>.

Please add a custom "myapp://" URL scheme to cefsimple that serves
HTML content from C++.

Use the instructions in @cef/tools/claude/CLAUDE_CLIENT_INSTRUCTIONS.md

The CEF wiki is available at /path/to/cef_wiki (if cloned locally)
```

--------------------------------

### Generate and Build Breakpad Tools

Source: https://github.com/chromiumembedded/cef/blob/master/docs/crash_reporting.md

Use GN to generate the build files and Ninja to compile the necessary crash analysis utilities.

```sh
gn gen out/Release
ninja -C out/Release dump_syms minidump_stackwalk
```

--------------------------------

### Create project directories

Source: https://github.com/chromiumembedded/cef/blob/master/docs/master_build_quick_start.md

Initialize the required directory structure for the CEF build environment.

```sh
mkdir ~/code
mkdir ~/code/automate
mkdir ~/code/chromium_git
```

--------------------------------

### Retrieve JS Value

Source: https://github.com/chromiumembedded/cef/blob/master/docs/javascript_integration.md

Extract the underlying value from a CefV8Value using the Get*Value methods.

```cpp
CefString strVal = val.GetStringValue();
```

--------------------------------

### Initiate a CefURLRequest

Source: https://github.com/chromiumembedded/cef/blob/master/docs/general_usage.md

Create and start a network request using a CefRequest object and the custom client implementation.

```cpp
// Set up the CefRequest object.
CefRefPtr<CefRequest> request = CefRequest::Create();
// Populate |request| as shown above...

// Create the client instance.
CefRefPtr<MyRequestClient> client = new MyRequestClient();

// Start the request. MyRequestClient callbacks will be executed asynchronously.
CefRefPtr<CefURLRequest> url_request = CefURLRequest::Create(request, client.get(), nullptr);
// To cancel the request: url_request->Cancel();
```

--------------------------------

### Complete Update Workflow Steps

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CHROMIUM_UPDATE.md

Provides a step-by-step guide for the complete update workflow, including updating Chromium, running patch_updater.py, fixing patches with Claude, building CEF, fixing build errors, testing, and submitting changes.

```text
1. Update Chromium checkout to new version
    └─> automate-git.py or manual git commands

2. Run patch_updater.py
    └─> Captures failures in patch_output.txt

3. Fix patches with Claude
    ├─> Analyze output with analyze_patch_output.py → patch_analysis.txt
    ├─> Prompt: "@CLAUDE_PATCH_INSTRUCTIONS.md" with @patch_analysis.txt
    ├─> Claude fixes patches one by one
    └─> Verify: patch_updater.py runs clean

4. Build CEF
    └─> Captures errors in build_output.txt

5. Fix build errors with Claude
    ├─> Analyze output with analyze_build_output.py → build_analysis.txt
    ├─> Prompt: "@CLAUDE_BUILD_INSTRUCTIONS.md" with @build_analysis.txt
    ├─> Claude fixes errors one by one
    └─> Verify: Build succeeds

6. Test CEF
    └─> Run ceftests, cefclient, manual testing

7. Submit changes
    └─> Create PR with updated patches and fixes

```

--------------------------------

### Debug Test Failures

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLAUDE_TEST_INSTRUCTIONS.md

Example log entry documenting the investigation, cause, and resolution of a test timeout.

```text
Investigating NavigationTest.BackForward:

Issue: Test timeout (60s)
Cause: DestroyTest() not called after back navigation
Fix: Added DestroyTest() call in navigation complete handler

Verification: Ran 5 times, all passed (avg 234ms)
```

--------------------------------

### Build Bootstrap Executables (Windows)

Source: https://github.com/chromiumembedded/cef/blob/master/docs/sandbox_setup.md

Builds the bootstrap and bootstrapc targets using Ninja and creates a binary distribution. Ensure you have a local Chromium/CEF checkout and have set up the build environment.

```sh
# Discover what `args.gn` contents are required:
cd c:\path\to\chromium\src\cef
set GN_DEFINES=is_official_build=true
set GN_OUT_CONFIGS=Debug_GN_x64
python3 tools\gn_args.py

# Create or update the `chromium\src\out\Debug_GN_x64\args.gn` file with the specified contents.

# Build the bootstrap targets in the output directory:
cd c:\path\to\chromium\src
set DEPOT_TOOLS_WIN_TOOLCHAIN=0
gn gen out\Debug_GN_x64
ninja -C out\Debug_GN_x64 bootstrap bootstrapc

# Create a binary distribution for the bootstrap build:
cd c:\path\to\chromium\src\cef\tools
make_distrib.bat --allow-partial --sandbox --ninja-build --x64-build --no-archive --no-symbols --no-docs
```

--------------------------------

### Create Windows Build Configuration Helper

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CHROMIUM_UPDATE.md

Create this batch script on Windows to simplify regenerating build files after .gn changes. Ensure to replace the placeholder with your platform's build config.

```bat
set GN_OUT_CONFIGS=Debug_GN_x64
call cef_create_projects.bat
```

--------------------------------

### Auto-Generated Function Implementation

Source: https://github.com/chromiumembedded/cef/blob/master/tools/translator.README.txt

Example of an auto-generated function body containing a warning message for manual implementation.

```cpp
size_t CEF_CALLBACK frame_new_func(struct _cef_frame_t* self)
   {
     // BEGIN DELETE BEFORE MODIFYING
     // AUTO-GENERATED CONTENT
     #pragma message("Warning: " __FILE__ ": frame_new_func is not implemented")
     // END DELETE BEFORE MODIFYING
   }
```

--------------------------------

### Prototype Change Warning

Source: https://github.com/chromiumembedded/cef/blob/master/tools/translator.README.txt

Example of warning messages inserted into generated files when function prototypes change.

```cpp
// WARNING - CHANGED ATTRIBUTES
   //   REMOVED: const wchar_t* key
   //   ADDED:   int index
   // WARNING - CHANGED RETURN VALUE
   //   WAS: void
   //   NOW: int
   #pragma message("Warning: " __FILE__ ": MyFunction prototype has changed")
```

--------------------------------

### JavaScript Execution Examples

Source: https://github.com/chromiumembedded/cef/blob/master/docs/hands_on_tutorial.md

Various ways to use ExecuteJavaScript for alerts, DOM manipulation, and console logging.

```cpp
// Alert box
frame->ExecuteJavaScript("alert('Hello from C++!');", frame->GetURL(), 0);

// DOM manipulation
frame->ExecuteJavaScript(
    "var h1 = document.createElement('h1');"
    "h1.textContent = 'Added by CEF!';"
    "document.body.insertBefore(h1, document.body.firstChild);",
    frame->GetURL(), 0);

// Console log
frame->ExecuteJavaScript("console.log('CEF executed this');",
                         frame->GetURL(), 0);
```

--------------------------------

### View patch failure output

Source: https://github.com/chromiumembedded/cef/blob/master/docs/chromium_update.md

Example of the error output displayed when patch files have unresolved conflicts.

```text
--------------------------------------------------------------------------------
!!!! FAILED PATCHES, fix manually and run with --resave
content_2015:
  Hunk #4 FAILED at 4220.
  1 out of 5 hunks FAILED -- saving rejects to file content/browser/frame_host/render_frame_host_impl.cc.rej
storage_partition_1973:
  Hunk #1 FAILED at 167.
  1 out of 1 hunk FAILED -- saving rejects to file content/browser/shared_worker/shared_worker_service_impl.cc.rej
--------------------------------------------------------------------------------
```

--------------------------------

### Interpret Test Results

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLAUDE_TEST_INSTRUCTIONS.md

Example output format when running ceftests, showing pass/fail status and execution time.

```text
✓ Built ceftests (4m 12s)

Running: NavigationTest.*

Results:
✓ PASSED: NavigationTest.LoadURL (234 ms)
✓ PASSED: NavigationTest.Redirect (156 ms)
✗ FAILED: NavigationTest.BackForward (timeout 60s)

Summary: 2/3 passed

Investigating failure...
```

--------------------------------

### Initialize CEF Repository

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLAUDE_CHERRY_PICK_INSTRUCTIONS.md

Navigate to the CEF directory and fetch the latest upstream changes.

```bash
cd /path/to/chromium/src/cef
git fetch upstream master
```

--------------------------------

### View missing file error output

Source: https://github.com/chromiumembedded/cef/blob/master/docs/chromium_update.md

Example of the error output displayed when a patched file has been moved or deleted.

```cpp
--> Reading patch file /path/to/chromium_git/chromium/src/cef/patch/patches/content_mojo_3123.patch
--> Skipping non-existing file /path/to/chromium_git/chromium/src/content/public/browser/document_service_base.h
--> Applying patch to /path/to/chromium_git/chromium/src
(Stripping trailing CRs from patch; use --binary to disable.)
can't find file to patch at input line 5
...
Skip this patch? [y] 
Skipping patch.
2 out of 2 hunks ignored
--> Saving changes to /path/to/chromium_git/chromium/src/cef/patch/patches/content_mojo_3123.patch
Traceback (most recent call last):
  File "/path/to/chromium_git/chromium/src/cef/tools/patch_updater.py", line 294, in <module>
    raise Exception('Failed to add paths: %s' % result['err'])
Exception: Failed to add paths: fatal: pathspec '/path/to/chromium_git/chromium/src/content/public/browser/document_service_base.h' did not match any files
```

--------------------------------

### Build Commands by Platform

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CLIENT_DEVELOPMENT.md

Standard CMake build and execution commands for Windows, Linux, and macOS.

```bash
cmake -B build -G "Visual Studio 17 2022" -A x64 -DUSE_SANDBOX=OFF
cmake --build build --config Release --target cefsimple
build\tests\cefsimple\Release\cefsimple.exe
```

```bash
cmake -B build
cmake --build build --target cefsimple
build/tests/cefsimple/cefsimple
```

```bash
cmake -B build -G Xcode
cmake --build build --config Release --target cefsimple
open build/tests/cefsimple/Release/cefsimple.app
```

--------------------------------

### Starting Build Error Fixing with Analysis

Source: https://github.com/chromiumembedded/cef/blob/master/tools/claude/CHROMIUM_UPDATE.md

Use this prompt structure when patches are resolved and build error analysis is available.

```text
The patches are all fixed. Now please fix the build errors using the
instructions in @cef/tools/claude/CLAUDE_BUILD_INSTRUCTIONS.md

Build error analysis: @cef/tools/claude/build_analysis.txt
Target: cef
Out dir: Debug_GN_x64
```