Worked on the w3c/csswg-drafts repository, focusing on stabilizing front end behavior by addressing a critical bug in ResizeObserver’s size reporting. The work involved updating the initial lastReportedSizes to improve the accuracy and reliability of element size measurements, directly reducing layout instability during dynamic resizes. Emphasized thorough regression checks and code review to ensure stability across the resize measurement path, laying groundwork for future enhancements. Utilized JavaScript and front end development skills to deliver a targeted fix rather than new features, prioritizing measurement correctness and reliability in the codebase. The approach reflected careful attention to detail and robust engineering practices.