diff --git a/config/karma.config.js b/config/karma.config.js
index eb082dd28bfdff962770e4a7101ce5a986b41c24..40c58e7771d8a5188fe97415f2cac841be107224 100644
--- a/config/karma.config.js
+++ b/config/karma.config.js
@@ -13,6 +13,8 @@ if (webpackConfig.plugins) {
   });
 }
 
+webpackConfig.devtool = 'cheap-inline-source-map';
+
 // Karma configuration
 module.exports = function(config) {
   var progressReporter = process.env.CI ? 'mocha' : 'progress';
diff --git a/config/webpack.config.js b/config/webpack.config.js
index c77b1d6334cfbdeea72ad81803cc81402aa2df22..89ef30a972e8ea5c40ae318308ecfc9fff29c2e8 100644
--- a/config/webpack.config.js
+++ b/config/webpack.config.js
@@ -74,8 +74,6 @@ var config = {
     chunkFilename: IS_PRODUCTION ? '[name].[chunkhash].chunk.js' : '[name].chunk.js',
   },
 
-  devtool: 'cheap-module-source-map',
-
   module: {
     rules: [
       {