diff --git a/includes/Data/Patterns.php b/includes/Data/Patterns.php
index 849a02d0f..c0950b65e 100644
--- a/includes/Data/Patterns.php
+++ b/includes/Data/Patterns.php
@@ -358,6 +358,7 @@ public static function get_theme_step_patterns_from_step( $step, $squash = false
 		}
 
 		$pattern_slugs = self::get_theme_step_patterns()[ $active_theme ][ $step ];
+		$block_patterns = $squash ? '' : array();
 
 		foreach ( array_keys( $pattern_slugs ) as $pattern_slug ) {
 			if ( true !== $pattern_slugs[ $pattern_slug ]['active'] ) {