Worked on the gui-cs/Terminal.Gui repository to address rendering issues related to wide-character text in terminal user interfaces. Focused on improving the reliability of UI rendering when attribute changes occur, specifically by fixing a bug that caused stale attributes to appear in continuation cells. Utilized C# programming, debugging, and unit testing to implement a targeted solution that marks affected cells as dirty, ensuring accurate visual updates. Added regression tests to validate the fix and enhance test coverage, contributing to a more robust rendering pipeline. The work emphasized stability and correctness in handling wide-character scenarios within the Terminal.Gui codebase.