Developers frequently get into difficult bundling difficulties while utilizing Expo Router in a React Native project on macOS, particularly on the iOS simulator. The ".plugins is not a valid Plugin property" error is a common problem that might prevent development from moving forward. Compatibility issues between Node.js versions, Babel setups, or missing dependencies like babel-preset-expo could be the cause of this error. It's a challenging problem to fix because some developers continue to see issues even after upgrading configurations, downgrading Node, and cleaning caches. To fix this issue and increase app stability, follow these tried-and-true troubleshooting procedures.