From 59b51e0b0d3378b1c09567b616e8b64e8bcc24ea Mon Sep 17 00:00:00 2001
From: Joe Haddad <timer150@gmail.com>
Date: Thu, 27 Sep 2018 09:13:27 -0400
Subject: [PATCH] Output CSS sourcemaps in separate file (#5131)

* Output CSS sourcemaps in separate file

* explain options
---
 config/webpack.config.prod.js | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/config/webpack.config.prod.js b/config/webpack.config.prod.js
index 87b61980eac..8fe4f6189c6 100644
--- a/config/webpack.config.prod.js
+++ b/config/webpack.config.prod.js
@@ -158,7 +158,17 @@ module.exports = {
         sourceMap: shouldUseSourceMap,
       }),
       new OptimizeCSSAssetsPlugin({
-        cssProcessorOptions: { parser: safePostCssParser },
+        cssProcessorOptions: {
+          parser: safePostCssParser,
+          map: {
+            // `inline: false` forces the sourcemap to be output into a
+            // separate file
+            inline: false,
+            // `annotation: true` appends the sourceMappingURL to the end of
+            // the css file, helping the browser find the sourcemap
+            annotation: true,
+          },
+        },
       }),
     ],
     // Automatically split vendor and commons