Worked on the lfnovo/open-notebook repository to deliver two front end features focused on enhancing user experience and productivity. Developed fullscreen modes for dialogs and the Markdown editor, implementing dynamic height adjustments and robust state management using React, JavaScript, and TypeScript. Integrated MutationObserver to synchronize fullscreen behavior and ensure state resets on dialog closure. Improved the notebook page’s responsiveness by enabling horizontal scrolling on small viewports and refining the desktop chat column layout. These updates addressed editing focus, cross-device usability, and collaboration, resulting in a more consistent and efficient note-taking environment without introducing any new bugs during the development period.