In the technology-dominated current world, web applications must function smoothly across various user environments. It can be achieved only if proper testing is done. Firefox Browser Online is a tool in this array that provides a robust platform to simulate real-world user interactions in a controlled browser environment. Using Firefox Browser Online’s capabilities, testers and developers can test application behavior under a wide range of conditions and thus find issues, bottlenecks, and inconsistencies at the very earliest stage of the development life cycle. By gaining an in-depth understanding of…