In September 2025, Sun Shin developed initial Keyboard Lock support within the Fullscreen API for the achristensen07/WebKit repository. This feature introduced a browser-level keyboard lock mode that modifies Escape key behavior during fullscreen sessions, enhancing user control and security. Sun Shin implemented the functionality using JavaScript and HTML, leveraging Browser API and event handling expertise to ensure seamless integration with existing fullscreen logic. Comprehensive tests were added to verify correct behavior and lay the groundwork for future improvements. The work addressed a nuanced aspect of fullscreen user experience, providing a solid technical foundation for further refinements in WebKit.