Resolving 'Starting the development server...' Hang in Webpack 5 Projects
After upgrading a project from webpack 4 to webpack 5 (webpack@^5.64.4, webpack-dev-server@^4.6.0), running npm start results in the terminal hanging at Starting the development server..., and the browser shows a blank page at localhost:3000.
Diagnosing Common Causes
Port Conflict
The default port for webpack-dev-server is 3000. Check if anothe ...
Posted on Sat, 09 May 2026 05:23:11 +0000 by sy-co