Worked on the FreeTubeApp/FreeTube repository, focusing on front end development to enhance user experience and internationalization. Addressed multilingual correctness by implementing locale-aware profile name sorting using JavaScript’s Intl.Collator, ensuring accurate alphabetical ordering across languages and handling edge cases with case sensitivity. Improved fullscreen video playback by repositioning UI popups to prevent them from obscuring video titles, directly impacting usability. Delivered a feature aligning popup background opacity with YouTube’s design, leveraging CSS and design token reuse for scalable UI consistency. Maintained strong commit traceability and thorough testing, prioritizing accessibility, visual polish, and regression minimization throughout the development process.