[FIXED] Selenium. Bring-up window on the front

Issue

If you run the following code, then at each iteration of the cycle, the browser will bring up on the front and get focus.

public class Program
{
  private static void Main()
  {
    var driver = new ChromeDriver();
    driver.Navigate().GoToUrl("https://i.imgur.com/cdA7SBB.jpg");
    for (int i = 0; i < 100; i++)
    {
      var ss = ((ITakesScreenshot)driver).GetScreenshot();
      ss.SaveAsFile("D:/imgs/i.jpg");
    }
  }
}

The question is: why does this happen and can it be turned off? headless mod does not fit.

It seems that this always happens when Selenium needs to save / read the file or start the process.

Solution

To take a screenshot, chromedriver activates the window. It's by design and there's no option to avoid it even though it's technically possible. For the relevant sources have a look at window_commands.cc.

You could however avoid the effect by moving the window off-screen:

driver.Manage().Window.Position = new Point(-32000, -32000);

or by launching the browser off-screen:

var options = new ChromeOptions();
options.AddArgument("--window-position=-32000,-32000");

UPDATE

You can avoid the activation by taking the screenshot directly via the devtool API. Here's a class to override GetScreenshot:

using OpenQA.Selenium;
using OpenQA.Selenium.Chrome;
using OpenQA.Selenium.Remote;
using JObject = System.Collections.Generic.Dictionary<string, object>;


class ChromeDriverEx : ChromeDriver
{
    public ChromeDriverEx(ChromeOptions options = null) 
        : base(options ?? new ChromeOptions()) {
        var repo = base.CommandExecutor.CommandInfoRepository;
        repo.TryAddCommand("send", new CommandInfo("POST", "/session/{sessionId}/chromium/send_command_and_get_result"));
    }

    public new Screenshot GetScreenshot() {
        object response = Send("Page.captureScreenshot", new JObject {{"format", "png"}, {"fromSurface", true}});
        string base64 = (string)((JObject)response)["data"];
        return new Screenshot(base64);
    }

    protected object Send(string cmd, JObject args) {
        return this.Execute("send",  new JObject {{"cmd", cmd}, {"params", args}}).Value;
    }
}

usage:

var driver = new ChromeDriverEx();
driver.Url = "https://stackoverflow.com";
driver.GetScreenshot().SaveAsFile("/tmp/screenshot.png");
driver.Quit();

Answered By - Florent B.