Worked on the electron/electron repository to deliver a new animated vibrancy duration feature for macOS BrowserWindow, enhancing UI polish and developer control. The project involved adding an optional animation duration parameter to the setVibrancy method, enabling smooth fading transitions for vibrancy effects in Electron applications. This required updates to the C++ API, modifications to native macOS window handling using Objective-C, and comprehensive documentation improvements to guide developers in adopting the new capability. The work aligned with macOS platform UX expectations, providing developers with finer control over window aesthetics while maintaining consistency with native application behaviors and performance standards.