Worked on stabilizing navigation within the DuckDuckGo browser in the apple-browsers repository, focusing on resolving crashes related to duck:// URLs loaded in iframes. Addressed a bug by refactoring the navigation policy so that the WKNavigationDelegate completion handler is always invoked for duck:// navigations, including those inside iframes, rather than only for main-frame requests. This targeted update, implemented in Swift and leveraging WKWebView for iOS development, isolated the fix to navigation policy handling, minimizing risk to other browser functionality. The change improved browser reliability by preventing hangs and crashes, and was validated through focused protocol navigation testing.