fix: transform JS bigint literal XXXn to BigInt("XXX")

config/babel-plugin-transform-bigint.js

@@ -0,0 +1,20 @@
+// babel-plugin-transform-bigint.js
+module.exports = function(babel) {
+  const { types: t } = babel;
+
+  return {
+    name: "babel-plugin-transform-bigint",
+    visitor: {
+      BigIntLiteral(path) {
+        const value = path.node.value;
+        // Replace BigInt literal with a call to BigInt constructor
+        path.replaceWith(
+          t.callExpression(
+            t.identifier('BigInt'),
+            [t.stringLiteral(value)]
+          )
+        );
+      }
+    }
+  };
+};

config/webpack.config.js

@@ -429,6 +429,9 @@ module.exports = function (webpackEnv) {
                 // show incorrect code and set breakpoints on the wrong lines.
                 sourceMaps: shouldUseSourceMap,
                 inputSourceMap: shouldUseSourceMap,
+                plugins: [
+                  [require.resolve("./babel-plugin-transform-bigint.js")]
+                ],
               },
             },
             // "postcss" loader applies autoprefixer to our CSS.