diff --git a/backend/db/schema.rb b/backend/db/schema.rb
index 56b70a0..eee4568 100644
--- a/backend/db/schema.rb
+++ b/backend/db/schema.rb
@@ -158,7 +158,7 @@ ActiveRecord::Schema[8.0].define(version: 2026_09_22_040000) do
     t.index ["language_code"], name: "index_locales_on_language_code"
     t.index ["region_code"], name: "fk_rails_175159992c"
     t.index ["script_code"], name: "fk_rails_0b74ce96a8"
-    t.check_constraint "regexp_like(`variants`,_utf8mb4'^(([a-z0-9]{5,8}|[0-9][a-z0-9]{3})(-([a-z0-9]{5,8}|[0-9][a-z0-9]{3}))*)?$',_utf8mb4'c')", name: "locales_variants_check"
+    t.check_constraint "regexp_like(`variants`,_utf8mb4'^((([a-z0-9]{5,8}|[0-9][a-z0-9]{3})(-([a-z0-9]{5,8}|[0-9][a-z0-9]{3}))*(-x(-[a-z0-9]{1,8})+)?)|(x(-[a-z0-9]{1,8})+))?$',_utf8mb4'c')", name: "locales_variants_check"
   end
 
   create_table "material_export_items", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|