Fetch pre-made archives only on dialog open

src/client/components/AppHeader.vue

@@ -63,7 +63,7 @@
 </template>
 
 <script setup lang="ts">
-import { computed, onMounted, ref } from 'vue'
+import { computed, onMounted, ref, watch } from 'vue'
 import api from '../api'
 import { useStore } from '../store'
 import AppDialog from './AppDialog.vue'
@@ -72,9 +72,15 @@ const store = useStore()
 const downloadsVisible = ref<boolean>(false)
 const archives = computed(() => store.archives)
 
-onMounted(() => {
-  store.fetchArchives()
-})
+/**
+ * Fetch the list of archives when the dialog is opened.
+ * Do it only once to avoid unnecessary requests.
+ */
+watch(
+  downloadsVisible,
+  () => { store.fetchArchives() },
+  { once: true }
+)
 
 /**
  * Open the dialog.