diff --git a/gulpfile.js b/gulpfile.js
index 5b2ed651c..469b99ca4 100644
--- a/gulpfile.js
+++ b/gulpfile.js
@@ -751,15 +751,17 @@ function preprocessDefaultPreferences(content) {
   var preprocessor2 = require('./external/builder/preprocessor2.js');
   var licenseHeader = fs.readFileSync('./src/license_header.js').toString();
 
+  var GLOBALS = '/* eslint-disable */\n';
   var MODIFICATION_WARNING =
-    '//\n// THIS FILE IS AUTOMATICALLY GENERATED, DO NOT EDIT MANUALLY!\n//\n';
+    '//\n// THIS FILE IS GENERATED AUTOMATICALLY, DO NOT EDIT MANUALLY!\n//\n';
 
   content = preprocessor2.preprocessPDFJSCode({
     rootPath: __dirname,
     defines: DEFINES,
   }, content);
 
-  return licenseHeader + '\n' + MODIFICATION_WARNING + '\n' + content + '\n';
+  return (licenseHeader + '\n' + GLOBALS + '\n' + MODIFICATION_WARNING + '\n' +
+          content + '\n');
 }
 
 gulp.task('mozcentral-pre', ['buildnumber', 'locale'], function () {