diff --git a/config/webpack.config.dev.js b/config/webpack.config.dev.js
index e9d5a1f4946..ca232192934 100644
--- a/config/webpack.config.dev.js
+++ b/config/webpack.config.dev.js
@@ -116,7 +116,7 @@ module.exports = {
       // in development "style" loader enables hot editing of CSS.
       {
         test: /\.css$/,
-        loader: 'style!css!postcss'
+        loader: 'style!css?sourceMap!postcss'
       },
       // JSON is not enabled by default in Webpack but both Node and Browserify
       // allow it implicitly so we also enable it.