Worked on enhancing the reliability and stability of the ViewportComponent in the iTwin/appui repository by addressing a crash caused by zero-dimension parent containers. Introduced a ResizeObserver to monitor the container’s dimensions and implemented an initialization guard to delay viewport creation until valid width and height were reported. Updated the useEffect logic and associated tests to align with the new initialization flow, ensuring robust error handling and improved rendering behavior. Utilized React for component development and applied both JavaScript and TypeScript to reinforce frontend stability. The work focused on targeted bug resolution and thorough testing rather than new feature development.