Selenium 4 vs Selenium 3: Key Differences You Need to Know

Selenium is a widely used open-source tool for automating web applications across different browsers. With the release of Selenium 4, there have been significant updates and changes compared to its predecessor, Selenium 3. These changes aim to enhance the user experience, improve browser compatibility, and provide better testing capabilities for modern web applications. In this blog post, we will explore the key differences between Selenium 4 and Selenium 3 and understand how these updates impact automated testing. Additionally, we will provide insights into Selenium online courses, Selenium classes, and the benefits of obtaining a Selenium certificate.
Overview of Selenium 3
Before we dive into the differences between Selenium 4 and Selenium 3, let’s briefly review Selenium 3. Released in October 2016, Selenium 3 was a major upgrade from Selenium 2. It introduced several improvements, including enhanced browser support, an improved WebDriver API, and better stability. Selenium 3 was primarily focused on refining the WebDriver architecture and supporting the latest web technologies.
While Selenium 3 offered robust automation features, it lacked certain capabilities required for testing modern web applications effectively. This is where Selenium 4 steps in, addressing these limitations and bringing more powerful features to the table.
Key Differences Between Selenium 4 and Selenium 3

1. W3C WebDriver Standardization One of the most significant changes in Selenium 4 is the complete adoption of the W3C WebDriver standard. In Selenium 3, WebDriver implementations were partially aligned with the W3C standard, but the communication between the client and server used a JSON Wire Protocol, which often led to compatibility issues across different browsers. In Selenium 4, the WebDriver API has been fully standardized according to the W3C specifications. This means that the communication between the browser and the testing framework is more reliable and consistent, leading to fewer errors and better cross-browser compatibility. As a result, developers and testers can expect more stable automated tests across Chrome, Firefox, Edge, and other browsers.
2. New Relative Locators Selenium 4 introduces a new feature called Relative Locators (formerly known as Friendly Locators). This addition simplifies the process of locating elements on a web page. In Selenium 3, finding elements required more precise locators, such as XPath or CSS selectors, which could become cumbersome for dynamic web applications. With Selenium 4, you can now locate elements relative to other known elements using commands like above(), below(), toLeftOf(), toRightOf(), and near(). This allows for more flexible and readable test scripts. For example, instead of specifying a complex XPath, you can use a relative locator to interact with an element based on its position relative to another element.
3. Enhanced Browser DevTools Integration Selenium 4 offers enhanced integration with Chrome DevTools and Firefox DevTools, providing testers with powerful tools for debugging and inspecting web applications. This feature allows developers and testers to simulate different network conditions, monitor performance, and capture logs directly from the browser. In Selenium 3, such capabilities were either limited or required third-party tools. With the DevTools Protocol integration, testers can now perform actions like intercepting network requests, emulating mobile devices, and modifying network speeds directly within the Selenium test script. This is particularly useful for performance testing and testing responsive designs.
4. Selenium IDE Improvements Selenium 4 brings significant updates to Selenium IDE, a tool that was reintroduced after being deprecated. The new Selenium IDE includes better cross-browser support, allowing users to record and run tests on multiple browsers. Selenium 3 had limited browser support for the IDE, making it less versatile for testers who needed to automate across different platforms. In Selenium 4, the IDE has been redesigned with enhanced recording capabilities, debugging tools, and test reporting features. Testers can now record tests more efficiently, making it easier to create and execute automated scripts without extensive programming knowledge.

5. Improved Grid Architecture
   The Selenium Grid is a tool used for parallel test execution across different machines and browsers. While Selenium 3 provided a functional Grid, it was complex to set up and maintain. Selenium 4 introduces a simplified and more powerful Grid architecture, making it easier to manage test execution.
   Selenium 4 Grid now supports Docker containers, which means that testers can set up and scale their Grid infrastructure quickly using containerization. The new Grid also features improved observability, providing users with more insights into test execution, making it easier to troubleshoot issues. This change is particularly beneficial for large-scale test automation projects.

6. Native Support for Chrome DevTools Protocol
   Selenium 4 provides native support for the Chrome DevTools Protocol, allowing testers to access advanced debugging tools directly from their Selenium scripts. This feature enables testers to capture network traffic, inspect performance metrics, and simulate different network conditions in real-time, which was not available in Selenium 3. This integration is especially useful for testing single-page applications (SPAs) and progressive web apps (PWAs), which require more in-depth monitoring and interaction.

7. Better Documentation and Support
   With the release of Selenium 4, the official documentation has been improved significantly. The new documentation provides more comprehensive examples, tutorials, and guides, making it easier for both beginners and experienced testers to learn and implement Selenium. Selenium 3’s documentation, while functional, was not as detailed or user-friendly.
   Why Should You Upgrade to Selenium 4?
   Upgrading to Selenium 4 is highly recommended for several reasons. First, it offers better browser compatibility and more stable test execution, thanks to the adoption of the W3C WebDriver standard. Second, the new features like relative locators, enhanced DevTools integration, and improved Selenium Grid make testing modern web applications easier and more efficient. Lastly, the improved documentation and ongoing community support ensure that you have access to the latest resources and best practices for your test automation projects.
   Selenium Online Courses and Certifications
   As automation testing continues to evolve, staying up-to-date with the latest tools and frameworks is essential for professionals in the field. Learning Selenium is one of the most effective ways to advance your career in test automation, and there are numerous Selenium online courses available that can help you master the tool. Whether you are new to Selenium or looking to upgrade your skills, these courses provide comprehensive training on Selenium 4, covering everything from basic concepts to advanced test automation techniques.
   Benefits of Selenium Online Courses:
   Flexible Learning: Selenium online courses allow you to learn at your own pace, fitting your studies around your schedule. This is particularly useful for working professionals who need to balance learning with their job responsibilities.
   Up-to-date Content: The courses are regularly updated to include the latest features of Selenium 4, ensuring that you learn the most current tools and techniques.
   Practical Experience: Most Selenium classes offer hands-on training, giving you practical experience with real-world testing scenarios. This helps build your confidence in writing and executing automated test scripts.
   Certification: Upon completing a Selenium course, you can earn a Selenium certificate, which can significantly enhance your resume and make you stand out to potential employers. Many job listings for test automation roles require or prefer candidates with Selenium certification, so earning this credential can open up new career opportunities.
   What You Will Learn in Selenium Classes
   Online Selenium classes typically cover the following topics:
   Basics of Selenium WebDriver and how to set up a test automation environment
   Writing and executing test scripts using Selenium
   Understanding different locator strategies, including the new Relative Locators in Selenium 4
   Using Selenium Grid for parallel test execution
   Advanced topics like integrating Selenium with TestNG or JUnit
   Debugging and troubleshooting common issues in test automation
   Best practices for designing and maintaining automated test frameworks
   Importance of a Selenium Certificate
   Obtaining a Selenium certificate demonstrates your proficiency in using the tool for web application testing. A certification not only validates your skills but also boosts your credibility as a test automation professional. Many organizations look for certified testers who can quickly contribute to their automation projects without the need for extensive training.
   Moreover, holding a Selenium certificate can lead to better job prospects and higher salaries. Companies are increasingly looking for professionals who are up-to-date with the latest tools and frameworks in automation, and a certification in Selenium 4 can make you more competitive in the job market.
   Conclusion
   The transition from Selenium 3 to Selenium 4 brings a host of new features and improvements that make it easier and more efficient to automate web application testing. The adoption of the W3C WebDriver standard, new relative locators, and enhanced DevTools integration are just a few of the highlights that set Selenium 4 apart from its predecessor. For testers and developers, upgrading to Selenium 4 is a logical step towards better testing outcomes.
   If you're looking to stay ahead in the automation testing field, consider enrolling in Selenium online courses or Selenium classes. These courses not only teach you the latest features of Selenium 4 but also provide the practical skills needed to succeed in test automation. By earning a Selenium certificate, you can further boost your career prospects and demonstrate your expertise in one of the most popular automation tools on the market.