Worked on the scality/core-ui repository to enhance the reliability of the ConstrainedText component by delivering targeted unit tests. Focused on verifying that the component correctly renders text, numeric, and JSX content, the work addressed both mixed content handling and user interface stability. The approach included comprehensive testing of tooltip behavior for overflowing text, ensuring a consistent user experience and reducing the risk of regressions in core UI areas. Leveraged React for component structure and utilized JavaScript and TypeScript for test implementation, emphasizing front end development and testing best practices to strengthen correctness guarantees across critical rendering scenarios.