added StoragePersist.vue to prompt user/browser to persist our data permanently and not evict it to free memory

src/App.vue

@@ -4,6 +4,7 @@ import {Options, Vue} from 'vue-class-component';
 import DocumentLocaleSetter from '@/components/locale/DocumentLocaleSetter.vue';
 import NavBar from '@/components/NavBar.vue';
 import LocaleSaver from '@/components/locale/LocaleSaver.vue';
+import StoragePersist from '@/components/StoragePersist.vue';
 
 @Options({
   name: 'App',
@@ -12,6 +13,7 @@ import LocaleSaver from '@/components/locale/LocaleSaver.vue';
     LocaleSaver,
     NavBar,
     RouterView,
+    StoragePersist,
   },
 })
 export default class App extends Vue {
@@ -23,6 +25,7 @@ export default class App extends Vue {
   <div class="d-flex flex-column h-100 w-100">
     <LocaleSaver/>
     <DocumentLocaleSetter/>
+    <StoragePersist/>
     <NavBar/>
     <RouterView class="flex-grow-1"/>
   </div>

src/components/StoragePersist.vue

@@ -0,0 +1,18 @@
+<script lang="ts">
+import {Options, Vue} from 'vue-class-component';
+import {toast} from 'vue3-toastify';
+
+@Options({name: 'StoragePersist'})
+export default class StoragePersist extends Vue {
+  async mounted(): Promise<void> {
+    if (!navigator.storage) {
+      toast.error(this.$t('localStoragePersistNotSupported'), {autoClose: false, theme: 'colored'});
+    } else {
+      await navigator.storage.persist();
+    }
+  }
+}
+</script>
+
+<template>
+</template>

src/locale/de.ts

@@ -11,6 +11,7 @@ export const messagesDe = {
     },
   },
   locale: messagesEn.locale,
+  localStoragePersistNotSupported: 'Lokaler Speicher wird nicht permanent. Das könnte in längere Wartezeiten verursachen!',
   manga: {
     chapters: {
       newCount: '#Neue Kapitel',

src/locale/en.ts

@@ -12,6 +12,7 @@ export const messagesEn = {
     'de': 'Deutsch',
     'en': 'English',
   },
+  localStoragePersistNotSupported: 'Locale storage will not be persisted. This could result in longer loading times!',
   manga: {
     chapters: {
       newCount: '#new chapters',