Worked on the microsoft/magentic-ui repository to address a persistent issue affecting automated UI testing reliability on macOS. Focused on debugging and network configuration, the developer resolved browser connection timeouts in Playwright tests running within Docker containers by switching the hostname from localhost to 127.0.0.1 and enforcing IPv4 connections. This targeted fix eliminated macOS-specific networking flakiness, resulting in more stable test execution and faster feedback cycles in continuous integration pipelines. The solution was implemented in Python and leveraged Docker and Playwright, demonstrating a methodical approach to cross-platform test stability and a strong understanding of containerized network environments.