Migrating from Selenium Library to Browser Library in Robot Framework: A Smarter Choice

Automation testing is a cornerstone of software quality assurance, and selecting the right tools can significantly impact efficiency, scalability, and long-term maintenance. With the growing complexity of web applications, the need for faster, more reliable test execution has never been greater. Recognizing these challenges, our team recently transitioned from the Selenium Library to the Browser Library in Robot Framework. This strategic shift was driven by extensive research and a proof of concept (POC) aimed at validating performance, reliability, and maintainability. 

Why Migrate from Selenium Library to Browser Library? 

Selenium has long been the go-to framework for browser automation, powering over 80% of test automation projects worldwide (Source: Stack Overflow Developer Survey). However, as modern applications demand faster execution times, better stability, and enhanced support for dynamic elements, Selenium’s limitations have become more apparent. Here’s why we found the Browser Library (built on Playwright) to be a superior alternative: 

1. Faster Execution & Lower Resource Consumption 

Speed is a crucial factor in test automation. Studies indicate that Playwright-based tests run up to 50% faster than Selenium-based tests due to its WebSocket-based communication instead of the WebDriver protocol (Source: Microsoft Playwright Benchmark Report). This results in: 

• Lower CPU and memory usage, optimizing resource allocation 
• Quicker test runs, significantly reducing feedback loops 
• More efficient parallel execution, improving CI/CD pipeline performance 

2. Native Support for Multiple Browsers 

Unlike Selenium, which requires separate Web Drivers for different browsers, the Browser Library provides native support for Chromium, Firefox, WebKit, and Microsoft Edge without additional configurations. This eliminates: 

• WebDriver version mismatches that frequently cause failures 
• Lengthy setup and maintenance efforts 
• Incompatibility issues across browser versions 

3. Built-in Auto-Wait Mechanism for Stability 

A common challenge with Selenium is handling dynamic elements that require explicit or implicit waits. According to Sauce Labs’ Test Automation Trends Report, 40% of test failures in Selenium are due to timing issues. The Browser Library automatically waits for elements to be ready before interacting with them, leading to: 

• Reduced flakiness in tests 
• Elimination of unnecessary sleep/wait statements 
• Higher test stability and reliability 

4. Improved Handling of Shadow DOM and iFrames 

With the rise of modern UI frameworks, Shadow DOM and iFrames are increasingly used for encapsulation. Selenium often struggles with these elements, requiring complex workarounds. The Browser Library, on the other hand, provides native support, making it easier to: 

• Interact seamlessly with Shadow DOM elements 
• Automate tests involving multiple iFrames 
• Avoid complex scripts and third-party dependencies 

5. Headless Mode and Multi-Context Testing 

More than 60% of automated tests in CI/CD pipelines run in headless mode for better efficiency (Source: DevOps Testing Report). The Browser Library excels in this by: 

• Executing tests in headless mode with better performance 
• Supporting multi-context testing, allowing parallel browser interactions 
• Providing better debugging capabilities compared to Selenium 

6. Built-in Network Interception and Request Mocking 

Testing backend-dependent scenarios is a significant challenge in Selenium. The Browser Library introduces network interception and request mocking, enabling: 

• API testing within the browser 
• Simulated network conditions (latency, failures, etc.) 
• Validation of front-end behavior without relying on real backend responses 

This capability is particularly useful for front-end testing teams aiming to reduce dependencies on backend availability. 

 POC on Browser Library Implementation 

To validate the benefits of the Browser Library, we conducted a detailed POC comparing it with Selenium Library on key performance metrics: 

Key Findings: 

• Test execution speed improved by an average of 40%. 
• Test flakiness reduced significantly due to auto-wait features. 
• Shadow DOM and iFrame handling was seamless, eliminating workarounds. 
• Network interception and request mocking provided added flexibility.
• Final Decision: Moving Forward with Browser Library 

Based on these compelling results, we have officially migrated to the Browser Library, leading to: 

• Faster, more stable test execution 
• Easier maintenance with fewer dependencies 
• Enhanced debugging and troubleshooting capabilities 
• Improved efficiency in CI/CD pipelines 

 Should You Migrate? 

If your team is still using Selenium Library in Robot Framework, here’s why you should consider migrating: 

• You’re experiencing slow test execution and high flakiness. 
• Your application relies heavily on dynamic content, Shadow DOM, or iFrames. 
• You need better cross-browser support with simplified setup. 
• You require network interception and request mocking for testing complex scenarios. 

With the increasing demand for faster, more reliable test automation, the Browser Library emerges as a smarter choice for modern teams. Ready to upgrade your test automation strategy? Get in touch with our experts now!