fix(nextjs): revert automatic development conditions

The automatic addition of 'development' to webpack conditionNames causes
issues with Next.js client boundaries due to 'export *' statements in
ESM builds. Reverted to manual config in test app only.

Author: BYK

dev-packages/e2e-tests/test-applications/nextjs-15-spotlight/next.config.js

@@ -7,6 +7,20 @@ const nextConfig = {
   env: {
     NEXT_PUBLIC_SENTRY_SPOTLIGHT: 'true',
   },
+
+  // Configure webpack to use 'development' export condition in dev mode
+  // This enables Sentry SDK's development-only features like Spotlight auto-enablement
+  // Note: This is required because Next.js doesn't use the 'development' condition by default
+  webpack: (config, { dev }) => {
+    if (dev) {
+      config.resolve = config.resolve || {};
+      config.resolve.conditionNames = [
+        'development',
+        ...(config.resolve.conditionNames || ['import', 'module', 'browser', 'require', 'node', 'default']),
+      ];
+    }
+    return config;
+  },
 };
 
 module.exports = withSentryConfig(nextConfig, {

packages/nextjs/src/config/webpack.ts

@@ -97,16 +97,6 @@ export function constructWebpackConfigFunction({
     // `newConfig.module.rules` is required, so we don't have to keep asserting its existence
     const newConfig = setUpModuleRules(rawNewConfig);
 
-    // In development mode, add 'development' to resolve conditions so that
-    // @sentry/* packages use their development exports (which include features like Spotlight auto-enablement)
-    if (isDev) {
-      newConfig.resolve = newConfig.resolve || {};
-      newConfig.resolve.conditionNames = [
-        'development',
-        ...(newConfig.resolve.conditionNames || ['import', 'module', 'browser', 'require', 'node', 'default']),
-      ];
-    }
-
     // Add a loader which will inject code that sets global values
     addValueInjectionLoader({
       newConfig,