diff --git a/webpack.config.js b/webpack.config.js
index 237e124da191f353423df8b5f8dd206b96fb92db..a9424dba86c62a0e18a086b693255f0716623b8e 100644
--- a/webpack.config.js
+++ b/webpack.config.js
@@ -112,7 +112,7 @@ module.exports = [
                 chunks: ['lib', 'gui'],
                 template: 'src/playground/index.ejs',
                 title: 'Scratch 3.0 GUI',
-                sentryConfig: '"' + process.env.SENTRY_CONFIG + '"'
+                sentryConfig: process.env.SENTRY_CONFIG ? '"' + process.env.SENTRY_CONFIG + '"' : null
             }),
             new HtmlWebpackPlugin({
                 chunks: ['lib', 'blocksonly'],