Its biggest advantage is that it is very customizable.
Selenium HQ supports multiple programming languages and integrates easily with other systems, offering flexibility and customization through its open-source nature. It enhances manual testing efficiency by allowing simultaneous executions across browsers. Strong community support boosts usability, while its automation of front-end tasks elevates web testing. Despite a complex Selenium Grid setup and stability issues with Internet Explorer, improvements in handling frames, XPath tools, and better integration are needed.