Commit c164775b051 for woocommerce

commit c164775b05180bdc1c3479b711bd34ee8f0ad7c5
Author: Yuliyan Slavchev <yuliyan.slavchev@gmail.com>
Date:   Thu Aug 27 12:37:54 2026 +0300

    Validate the return of the email editor preload routes filter (#68021)

diff --git a/packages/php/email-editor/changelog/fix-preload-routes-filter-guard b/packages/php/email-editor/changelog/fix-preload-routes-filter-guard
new file mode 100644
index 00000000000..f4d5a4a2564
--- /dev/null
+++ b/packages/php/email-editor/changelog/fix-preload-routes-filter-guard
@@ -0,0 +1,4 @@
+Significance: patch
+Type: fix
+
+Guard against non-array return values from the woocommerce_email_editor_preload_rest_api_routes filter.
diff --git a/packages/php/email-editor/src/Engine/class-assets-manager.php b/packages/php/email-editor/src/Engine/class-assets-manager.php
index 7e3a7de0198..555fdb5087b 100644
--- a/packages/php/email-editor/src/Engine/class-assets-manager.php
+++ b/packages/php/email-editor/src/Engine/class-assets-manager.php
@@ -251,6 +251,10 @@ class Assets_Manager {
 		 */
 		$routes = apply_filters( 'woocommerce_email_editor_preload_rest_api_routes', $routes, $post_type, $post_id );

+		if ( ! is_array( $routes ) ) {
+			$routes = array();
+		}
+
 		$preload_data = array_reduce(
 			$routes,
 			'rest_preload_api_request',