Browser profile management in Selenium Java - Build an Automation Script

Verify browser profile settings are applied correctly in Selenium

Preconditions (2)

Step 1: Create a new Firefox profile with a custom preference (e.g., disable images loading)

Step 2: Launch Firefox browser using Selenium WebDriver with the created profile

Step 3: Navigate to a website that contains images (e.g., https://example.com)

Step 4: Verify that images are not loaded due to the profile setting

✅ Expected Result: Firefox browser launches with the custom profile settings applied, and images on the website do not load

Automation Requirements - Selenium WebDriver with Java

Assertions Needed:

Verify the browser is launched with the custom profile

Verify that images are not loaded on the webpage

Best Practices:

Use FirefoxProfile to set preferences before launching the browser

Use explicit waits if needed to ensure page load

Use Page Object Model if expanding tests

Close the browser properly after test

Automated Solution

Selenium Java

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.firefox.FirefoxDriver;
import org.openqa.selenium.firefox.FirefoxOptions;
import org.openqa.selenium.firefox.FirefoxProfile;
import org.openqa.selenium.support.ui.ExpectedConditions;
import org.openqa.selenium.support.ui.WebDriverWait;

import java.time.Duration;

public class BrowserProfileTest {
    public static void main(String[] args) {
        // Set system property for geckodriver path if needed
        // System.setProperty("webdriver.gecko.driver", "/path/to/geckodriver");

        // Create Firefox profile
        FirefoxProfile profile = new FirefoxProfile();
        // Disable image loading: set preference to 2 (block images)
        profile.setPreference("permissions.default.image", 2);

        // Set Firefox options with profile
        FirefoxOptions options = new FirefoxOptions();
        options.setProfile(profile);

        // Initialize WebDriver with options
        WebDriver driver = new FirefoxDriver(options);

        try {
            // Navigate to example.com
            driver.get("https://example.com");

            // Wait for page to load
            WebDriverWait wait = new WebDriverWait(driver, Duration.ofSeconds(10));
            wait.until(ExpectedConditions.presenceOfElementLocated(By.tagName("body")));

            // Verify images are not loaded
            // Check if any <img> elements have naturalWidth > 0 (means loaded)
            boolean imagesLoaded = (Boolean) ((org.openqa.selenium.JavascriptExecutor) driver).executeScript(
                    "return Array.from(document.images).some(img => img.naturalWidth > 0);"
            );

            if (!imagesLoaded) {
                System.out.println("Test Passed: Images are blocked as per profile settings.");
            } else {
                System.out.println("Test Failed: Images are loaded despite profile settings.");
            }

        } finally {
            // Close browser
            driver.quit();
        }
    }
}

This test script creates a Firefox profile and sets a preference to block images from loading. It then launches Firefox with this profile using Selenium WebDriver.

After navigating to a website with images, it uses JavaScript execution to check if any images have loaded by checking their naturalWidth property.

If no images are loaded, the test prints a pass message; otherwise, it prints a fail message.

The script uses explicit waits to ensure the page body is present before checking images.

Finally, the browser is closed properly in a finally block to avoid resource leaks.

Common Mistakes - 3 Pitfalls

Not setting the Firefox profile in FirefoxOptions before creating the driver

Using Thread.sleep() instead of explicit waits

Checking image presence by counting <img> tags instead of verifying if images actually loaded

Bonus Challenge

Now add data-driven testing with 3 different Firefox profile preferences to block images, block JavaScript, and block CSS.

Show Hint

Practice

1. What is the main purpose of using a browser profile in Selenium WebDriver tests?

easy

A. To customize browser settings before launching for more realistic tests

B. To speed up the test execution by skipping browser startup

C. To automatically generate test reports after each test

D. To change the programming language of the test scripts

Solution

1. Step 1: Understand browser profile role

   A browser profile lets you set preferences like cookies, extensions, or homepage before starting the browser.

2. Step 2: Identify the main benefit

   This customization makes tests more reliable and realistic by simulating real user settings.

3. Final Answer:

   To customize browser settings before launching for more realistic tests -> Option A

4. Quick Check:

   Browser profile = customize settings [OK]

Hint: Browser profiles customize settings before browser launch [OK]

Common Mistakes:

• Thinking profiles speed up tests by skipping browser startup
• Confusing profiles with test report generation
• Believing profiles change test script language

2. Which of the following is the correct way to create a Firefox profile in Selenium Java?

easy

A. FirefoxProfile profile = FirefoxProfile();

B. FirefoxProfile profile = new FirefoxProfile;

C. FirefoxProfile profile = new FirefoxProfile();

D. FirefoxProfile profile = create FirefoxProfile();

Solution

1. Step 1: Recall Java object creation syntax

   In Java, to create a new object, use the 'new' keyword followed by the constructor with parentheses.

2. Step 2: Apply to FirefoxProfile

   The correct syntax is 'new FirefoxProfile();' with parentheses and semicolon.

3. Final Answer:

   FirefoxProfile profile = new FirefoxProfile(); -> Option C

4. Quick Check:

   Java new object = new ClassName(); [OK]

Hint: Use 'new ClassName();' to create objects in Java [OK]

Common Mistakes:

• Omitting parentheses after constructor
• Missing 'new' keyword
• Using incorrect method-like syntax

3. What will be the effect of the following Selenium Java code snippet?

FirefoxProfile profile = new FirefoxProfile();
profile.setPreference("browser.startup.homepage", "https://example.com");
FirefoxOptions options = new FirefoxOptions();
options.setProfile(profile);
WebDriver driver = new FirefoxDriver(options);
driver.get("about:home");
String currentUrl = driver.getCurrentUrl();

medium

A. The browser will open with homepage https://example.com and currentUrl will be 'https://example.com'

B. The browser will open with homepage https://example.com but currentUrl will be 'about:home'

C. The code will throw a runtime error due to incorrect profile usage

D. The browser will open with default homepage and currentUrl will be 'about:home'

Solution

1. Step 1: Understand profile preference setting

   The code sets the Firefox homepage preference to 'https://example.com' in the profile.

2. Step 2: Analyze driver.get call

   Despite the homepage setting, the code explicitly opens 'about:home' using driver.get(). So the browser opens that page.

3. Step 3: Check current URL

   Since driver.get("about:home") is called, currentUrl will be 'about:home', but the browser's homepage is set to 'https://example.com'.

4. Final Answer:

   The browser will open with homepage https://example.com but currentUrl will be 'about:home' -> Option B

5. Quick Check:

   driver.get overrides homepage for current URL [OK]

Hint: driver.get(url) opens that URL, ignoring homepage setting for current page [OK]

Common Mistakes:

• Assuming homepage setting overrides driver.get call
• Confusing currentUrl with homepage URL
• Thinking profile setting causes runtime error

4. Identify the error in this Selenium Java code snippet for setting a Chrome profile:

ChromeOptions options = new ChromeOptions();
options.setProfile("UserProfile");
WebDriver driver = new ChromeDriver(options);

medium

A. ChromeDriver cannot be created with options

B. The profile name must be passed as a File object, not a string

C. The code is correct and will run without errors

D. ChromeOptions does not have a setProfile method; use addArguments instead

Solution

1. Step 1: Check ChromeOptions API

   ChromeOptions class does not have a method named setProfile(). Profiles are set using addArguments or user-data-dir option.

2. Step 2: Correct way to set profile

   To use a Chrome profile, you add an argument like '--user-data-dir=path_to_profile' via options.addArguments().

3. Final Answer:

   ChromeOptions does not have a setProfile method; use addArguments instead -> Option D

4. Quick Check:

   ChromeOptions.setProfile() does not exist [OK]

Hint: Use addArguments for Chrome profiles, not setProfile [OK]

Common Mistakes:

• Calling non-existent setProfile method on ChromeOptions
• Passing profile name as string without path
• Assuming ChromeDriver can't accept options

5. You want to run multiple tests in parallel using Firefox with different user profiles to avoid data conflicts. Which approach correctly manages browser profiles in Selenium Java for this scenario?

hard

A. Create a new FirefoxProfile instance for each test with unique preferences and pass it to FirefoxOptions

B. Use the same FirefoxProfile instance for all tests to save memory

C. Launch Firefox without profiles and clear cookies manually after each test

D. Set the homepage preference globally once before all tests start

Solution

1. Step 1: Understand parallel test isolation

   Running tests in parallel requires isolated browser states to prevent data conflicts.

2. Step 2: Use separate profiles per test

   Creating a new FirefoxProfile per test with unique settings ensures each browser instance is independent.

3. Step 3: Pass profile via FirefoxOptions

   Each test passes its profile to FirefoxOptions, which launches Firefox with that profile.

4. Final Answer:

   Create a new FirefoxProfile instance for each test with unique preferences and pass it to FirefoxOptions -> Option A

5. Quick Check:

   Separate profiles per test = no conflicts [OK]

Hint: Use unique profiles per test for parallel runs [OK]

Common Mistakes:

• Sharing one profile instance across tests causing conflicts
• Not using profiles and relying on manual cookie clearing
• Setting homepage globally does not isolate tests