Index: frontend/node_modules/react-dev-utils/evalSourceMapMiddleware.js
===================================================================
--- frontend/node_modules/react-dev-utils/evalSourceMapMiddleware.js	(revision 9af201e94b5a79beb92a30858fc54de4bc3b9449)
+++ frontend/node_modules/react-dev-utils/evalSourceMapMiddleware.js	(revision 9af201e94b5a79beb92a30858fc54de4bc3b9449)
@@ -0,0 +1,47 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+'use strict';
+
+function base64SourceMap(source) {
+  const base64 = Buffer.from(JSON.stringify(source.map()), 'utf8').toString(
+    'base64'
+  );
+  return `data:application/json;charset=utf-8;base64,${base64}`;
+}
+
+function getSourceById(server, id) {
+  const module = Array.from(server._stats.compilation.modules).find(
+    (m) => server._stats.compilation.chunkGraph.getModuleId(m) == id,
+  );
+  return module.originalSource();
+}
+
+/*
+ * Middleware responsible for retrieving a generated source
+ * Receives a webpack internal url: "webpack-internal:///<module-id>"
+ * Returns a generated source: "<source-text><sourceMappingURL><sourceURL>"
+ *
+ * Based on EvalSourceMapDevToolModuleTemplatePlugin.js
+ */
+module.exports = function createEvalSourceMapMiddleware(server) {
+  return function handleWebpackInternalMiddleware(req, res, next) {
+    if (req.url.startsWith('/__get-internal-source')) {
+      const fileName = req.query.fileName;
+      const id = fileName.match(/webpack-internal:\/\/\/(.+)/)[1];
+      if (!id || !server._stats) {
+        next();
+      }
+
+      const source = getSourceById(server, id);
+      const sourceMapURL = `//# sourceMappingURL=${base64SourceMap(source)}`;
+      const sourceURL = `//# sourceURL=webpack-internal:///${module.id}`;
+      res.end(`${source.source()}\n${sourceMapURL}\n${sourceURL}`);
+    } else {
+      next();
+    }
+  };
+};