diff --git a/tools/webpack/packages.js b/tools/webpack/packages.js
index 9789103e2c..7ff8c33735 100644
--- a/tools/webpack/packages.js
+++ b/tools/webpack/packages.js
@@ -152,6 +152,8 @@ module.exports = function( env = { environment: 'production', watch: false, buil
 			new DefinePlugin( {
 				// Inject the `IS_GUTENBERG_PLUGIN` global, used for feature flagging.
 				'process.env.IS_GUTENBERG_PLUGIN': false,
+				// Inject the `IS_WORDPRESS_CORE` global, used for feature flagging.
+				'process.env.IS_WORDPRESS_CORE': true,
 				'process.env.FORCE_REDUCED_MOTION': JSON.stringify(
 					process.env.FORCE_REDUCED_MOTION
 				),