Jaeyong Lee enhanced XML and plaintext content-type handling in the hoppscotch/hoppscotch repository, focusing on improving how the application parses and displays various content types. He implemented explicit support for text/xml, refining MIME type mappings to ensure accurate editor language selection and correct parsing of XML and plaintext data in both requests and responses. Using Vue.js for front end development and leveraging JavaScript and TypeScript, Jaeyong improved editor behavior and syntax highlighting, reducing user-facing errors and misclassifications. This work strengthened the reliability of API exploration and code generation workflows by addressing parsing fidelity and editor usability for developers.