Worked on the laurent22/joplin repository to deliver an accessibility enhancement for the Mermaid chart export feature in the desktop application. Focused on aligning the export button with WCAG 2.2 standards, the work involved adding accessibility labels to improve usability for screen reader users and support keyboard navigation. The implementation was carried out using TypeScript and front end development best practices, with careful attention to accessibility requirements. The code changes were well-documented and maintainable, providing clear UI semantics and reducing accessibility risk for the vendor. This contribution addressed a tracked issue and delivered measurable business value through broader accessibility compliance.