Worked on enhancing the mui/base-ui repository by addressing a reliability issue with toast timers in React applications using TypeScript. Focused on improving user experience by ensuring that toast notifications resume their timers correctly when the browser window regains focus, which previously caused interruptions in timer behavior. Implemented window focus and blur event listeners to manage timer state, providing seamless transitions for users interacting with the application across different focus states. All changes were directly linked to the relevant issue for traceability, demonstrating a methodical approach to bug resolution and accountability in front end development with modern JavaScript frameworks and libraries.