Index: src/wp-includes/script-loader.php
===================================================================
--- src/wp-includes/script-loader.php	(revision 43891)
+++ src/wp-includes/script-loader.php	(working copy)
@@ -2284,10 +2284,9 @@
  * @global WP_Screen $current_screen
  */
 function wp_enqueue_registered_block_scripts_and_styles() {
-	global $current_screen;
+	$current_screen = get_current_screen();
+	$is_editor      = $current_screen instanceof WP_Screen && $current_screen->is_block_editor();
 
-	$is_editor = ( is_admin() && $current_screen->is_block_editor() );
-
 	$block_registry = WP_Block_Type_Registry::get_instance();
 	foreach ( $block_registry->get_all_registered() as $block_name => $block_type ) {
 		// Front-end styles.