diff --git a/src/components/archiveList.vue b/src/components/archiveList.vue
index 69b86fd..49a1161 100644
--- a/src/components/archiveList.vue
+++ b/src/components/archiveList.vue
@@ -61,6 +61,7 @@ This file is part of ArciveList.
             </div>
           </li>
           <li v-for="site in sites"
+              :key="site.id"
               class="accordion-item"
               data-accordion-item>
             <div class="accordion-title"