diff --git a/assets/config/webpack.config.development.js b/assets/config/webpack.config.development.js
--- a/assets/config/webpack.config.development.js
+++ b/assets/config/webpack.config.development.js
@@ -115,7 +115,7 @@
     static: {
       directory: path.resolve('./'),
       watch: {
-        ignored: /node_modules/
+        ignored: /(node_modules|.tox|.mypy)/
       }
     },
     // we do not use hot reloading here (as a framework like React needs to be used in order to fully benefit from that feature)