Worked on the paypal/paypal-messaging-components repository to enhance the security and reliability of the PayPal URI Popup flow. Addressed a critical bug by implementing robust domain and URL validation within the getURIPopup function, ensuring that only secure and valid PayPal domains could be opened. This approach mitigated the risk of unsafe URLs, directly improving user trust and the stability of the messaging component’s popup experience. Leveraged front end development skills with a focus on JavaScript and web security best practices, delivering an incremental fix that was fully traceable to both the relevant commit and the associated issue for transparency.