Chromium Browser opens up

[RawHut]

Is there an existing issue for this?

• I have searched both open/closed issues, no issue already exists.

CefSharp Version

133.0.6943.127 (Official Build) (64-bit)

Operating System

Windows 11

Architecture

x64

.Net Version

Net4.7.2

Implementation

WinForms

Reproduction Steps

Reproducible Steps:

Visit the Chrome Web Store online.
Click the "Add to Chrome" button.
A standard Chrome-style dialog box appears, asking for confirmation to add the extension.
Once confirmed, a new process (Chromium) starts with its light blue logo.
A complete browser session launches with the new extension installed.

Expected behavior

Expected Behavior:
The extension should load using a designated directory located in the user's local application data folder. The application combines the local application data path with the "Hyper X/Extensions" folder and adds this path to the command-line arguments with the "load-extension" option. However, after the extension is added, it appears that the CRX file is being deleted.

string extensionsDir = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "Hyper X", "Extensions"); settings.CefCommandLineArgs.Add("load-extension", extensionsDir);

Actual behavior

Actual Behavior:
After clicking the "Add to Chrome" button and confirming the installation, a new Chromium-based browser process launches with a light blue logo. This is unexpected, as the extension should load within the current process rather than starting a new instance of Chromium. Additionally, the CRX file is deleted, which prevents the extension from functioning as intended. Extra pice of info : I am auto downloading file via downloadhandler because it rediretcs to download the extension file when clicked on add extension

Regression?

No response

Known Workarounds

No response

Does this problem also occur in the CEF Sample Application

Yes using WPF/OffScreen command line args

Other information

No response

[RawHut]

Small update: I've managed to load extensions, though with some limitations. Extensions that require GUI modifications or setting changes aren't fully compatible with CEF, but those that don't require interaction load successfully. The process involves downloading the extension's .crx file, modifying its binary data to convert it into a .zip archive, and then using the command-line argument mentioned earlier to load the extracted extension.

[RawHut]

Is there an existing issue for this?

• I have searched both open/closed issues, no issue already exists.

CefSharp Version

133.0.6943.127 (Official Build) (64-bit)

Operating System

Windows 11

Architecture

x64

.Net Version

Net4.7.2

Implementation

WinForms

Reproduction Steps

Reproducible Steps:

Visit the Chrome Web Store online.
Click the "Add to Chrome" button.
A standard Chrome-style dialog box appears, asking for confirmation to add the extension.
Once confirmed, a new process (Chromium) starts with its light blue logo.
A complete browser session launches with the new extension installed.

Expected behavior

Expected Behavior:
The extension should load using a designated directory located in the user's local application data folder. The application combines the local application data path with the "Hyper X/Extensions" folder and adds this path to the command-line arguments with the "load-extension" option. However, after the extension is added, it appears that the CRX file is being deleted.

string extensionsDir = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "Hyper X", "Extensions"); settings.CefCommandLineArgs.Add("load-extension", extensionsDir);

Actual behavior

Actual Behavior:
After clicking the "Add to Chrome" button and confirming the installation, a new Chromium-based browser process launches with a light blue logo. This is unexpected, as the extension should load within the current process rather than starting a new instance of Chromium. Additionally, the CRX file is deleted, which prevents the extension from functioning as intended. Extra pice of info : I am auto downloading file via downloadhandler because it rediretcs to download the extension file when clicked on add extension

Regression?

No response

Known Workarounds

No response

Does this problem also occur in the CEF Sample Application

Yes using WPF/OffScreen command line args

Other information

No response

---

I've recently managed to load extensions in CEF, albeit with some limitations. Extensions that depend on GUI modifications or dynamic setting changes aren’t fully supported, but non-interactive extensions load successfully. The process involves:

1. Downloading the .crx File:
   Obtain the extension's .crx file.

2. Conversion to .zip:
   Modify its binary content (in memory) to convert it into a .zip archive, then extract the archive.

3. Loading via Command-Line:
   Use the --load-extension command-line argument to point CEF to the extracted extension directory.

Below is a sample Program.cs that demonstrates how to load an extracted extensions:

using CefSharp;
using CefSharp.WinForms;
using System;
using System.IO;
using System.Windows.Forms;

namespace CefExtensionLoader
{
    static class Program
    {
        [STAThread]
        static void Main()
        {
            // Initialize CefSharp settings with extension support
            var settings = new CefSettings();
            
            // Set the path to your extracted extension directory
            string extensionPath = @"C:\Path\To\Extracted\Extension";
            settings.CefCommandLineArgs.Add("load-extension", extensionPath);

            Cef.Initialize(settings);

            // Launch a browser instance
            var browser = new ChromiumWebBrowser("https://www.example.com");
            var form = new Form { Width = 1024, Height = 768 };
            form.Controls.Add(browser);
            Application.Run(form);
        }
    }

Note:

Extensions that require user interaction (GUI modifications or dynamic settings) may not function as expected.

This method only supports non-interactive extensions.

The conversion from .crx to .zip is necessary to extract the extension contents, which are then loaded via the command-line argument.

I'm looking forward to feedback and any suggestions for further improvements.

[amaitland]

Actual Behavior:
After clicking the "Add to Chrome" button and confirming the installation, a new Chromium-based browser process launches with a light blue logo. This is unexpected, as the extension should load within the current process rather than starting a new instance of Chromium. Additionally, the CRX file is deleted, which prevents the extension from functioning as intended. Extra pice of info : I am auto downloading file via downloadhandler because it rediretcs to download the extension file when clicked on add extension

Extensions aren't fully supported when using Alloy Styled browsers (which is currently the default). This is an upstream limitation.

You can change to using Chrome Styled browser which should support loading of extensions via the UI.

#4835 (comment)

Extensions that require user interaction (GUI modifications or dynamic settings) may not function as expected.

They should work with Chrome Styled browsers.