Jonathan Price worked on the Khan/perseus repository, focusing on improving keyboard and mouse interaction within unlimited graphs. He addressed a usability issue where keyboard navigation using arrow keys interfered with adding points by mouse click. By introducing an onDragStart callback in the React-based front end, Jonathan ensured that mouse drags and keyboard movements were correctly distinguished, preventing false drag states. He implemented and validated this behavior using both Storybook-based manual tests and unit tests in JavaScript and TypeScript. This targeted fix enhanced accessibility and editor workflow, allowing users to seamlessly navigate with the keyboard and add points without interruption.