Worked on the servo/servo repository to enhance desktop application usability for multi-monitor setups by implementing dynamic fullscreen functionality for the servoshell window. The solution shifted fullscreen determination from a static monitor reference at startup to runtime detection using Window.current_monitor(), allowing the window to adapt seamlessly as users move it between screens. This update addressed issue #45488, improving reliability and reducing confusion for users with multiple monitors. The work involved Rust programming and desktop application development, with manual validation performed due to the absence of dedicated servoshell tests. The changes delivered measurable improvements in cross-monitor window management and runtime state handling.