From 7385de9fc233cc78572951bb26055e996823bc44 Mon Sep 17 00:00:00 2001
From: Brian Vaughn <bvaughn@fb.com>
Date: Fri, 26 Jul 2019 10:13:07 -0700
Subject: [PATCH] react-devtools-core standalone bugfix: prevent electron crash

CSS source maps require the style-loader to use URL.createObjectURL (rather than just a <style> tag). For some reason, this crashes Electron's webview process, which completely breaks the embedded extension inside of Nuclide and other Electron apps. This commit turns (CSS) source maps off for production builds to avoid this crash.
---
 packages/react-devtools-core/webpack.standalone.js | 6 +++++-
 shells/browser/shared/webpack.config.js            | 2 +-
 shells/dev/webpack.config.js                       | 2 +-
 3 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/packages/react-devtools-core/webpack.standalone.js b/packages/react-devtools-core/webpack.standalone.js
index b21dfe5180b2e..9818479d1637b 100644
--- a/packages/react-devtools-core/webpack.standalone.js
+++ b/packages/react-devtools-core/webpack.standalone.js
@@ -57,7 +57,11 @@ module.exports = {
           {
             loader: 'css-loader',
             options: {
-              sourceMap: true,
+              // WARNING It's important that we disable CSS source maps for production builds.
+              // This causes style-loader to insert styles via a <style> tag rather than URL.createObjectURL,
+              // which in turn avoids a nasty Electron/Chromium bug that breaks DevTools in Nuclide.
+              // (Calls to URL.createObjectURL seem to crash the webview process.)
+              sourceMap: __DEV__,
               modules: true,
               localIdentName: '[local]___[hash:base64:5]',
             },
diff --git a/shells/browser/shared/webpack.config.js b/shells/browser/shared/webpack.config.js
index dd2acc1f3c917..def3e17b87d53 100644
--- a/shells/browser/shared/webpack.config.js
+++ b/shells/browser/shared/webpack.config.js
@@ -59,7 +59,7 @@ module.exports = {
           {
             loader: 'css-loader',
             options: {
-              sourceMap: true,
+              sourceMap: __DEV__,
               modules: true,
               localIdentName: '[local]___[hash:base64:5]',
             },
diff --git a/shells/dev/webpack.config.js b/shells/dev/webpack.config.js
index 6738e13117462..feefff86b346e 100644
--- a/shells/dev/webpack.config.js
+++ b/shells/dev/webpack.config.js
@@ -57,7 +57,7 @@ const config = {
           {
             loader: 'css-loader',
             options: {
-              sourceMap: true,
+              sourceMap: __DEV__,
               modules: true,
               localIdentName: '[local]___[hash:base64:5]',
             },