Update webpack config

.gitignore

@@ -4,3 +4,4 @@ node_modules/
 coverage/
 
 dist/*.js
+dist/*.map

package.json

@@ -1,6 +1,6 @@
 {
   "name": "mermaid",
-  "version": "7.1.0",
+  "version": "7.1.1",
   "description": "Markdownish syntax for generating flowcharts, sequence diagrams, class diagrams, gantt charts and git graphs.",
   "main": "dist/mermaid.core.js",
   "keywords": [

webpack.config.base.js

@@ -14,11 +14,7 @@ const jsRule = {
     loader: 'babel-loader',
     options: {
       presets: [
-        ['env', {
+        'env'
-          'targets': {
-            'browsers': ['last 3 versions']
-          }
-        }]
       ],
       plugins: ['lodash']
     }
@@ -52,6 +48,7 @@ export const jsConfig = () => {
     },
     module: {
       rules: [lodashRule, jsRule, lessRule]
-    }
+    },
+    devtool: 'source-map'
   }
 }