Text for 403 error is localized

I hacked the error.vue to catch the default 404 error message and to display a localized message instead. I found no better way to do it. Any ideas?

webapp/layouts/error.vue

@@ -2,7 +2,10 @@
   <div class="error-container">
     <base-icon class="error-icon" name="exclamation-circle" />
     <br />
-    <span class="error-message">{{ $t(error.message) }}</span>
+    <span v-if="error.message === 'This page could not be found'" class="error-message">
+      {{ $t('error-pages.default') }}
+    </span>
+    <span v-else class="error-message">{{ $t(error.message) }}</span>
     <br />
     <nuxt-link to="/">{{ $t('error-pages.back-to-index') }}</nuxt-link>
   </div>

webapp/locales/de.json

@@ -803,6 +803,8 @@
 	"profile-not-found": "Dieses Profil konnte nicht gefunden werden",
 	"back-to-index": "Zurück zur Startseite",
 	"post-not-found": "Dieser Beitrag konnte nicht gefunden werden",
-        "cannot-edit-post": "Dieser Beitrag kann nicht editiert werden"
+        "cannot-edit-post": "Dieser Beitrag kann nicht editiert werden",
+	"default": "Diese Seite konnte nicht gefunden werden",
+	"not-authorized": "Kein Zugang zu dieser Seite"
     }
 }

webapp/locales/en.json

@@ -803,7 +803,9 @@
     "profile-not-found": "This profile could not be found",
     "back-to-index": "Back to index page",
     "post-not-found": "This post could not be found",
-    "cannot-edit-post": "This post cannot be edited"
+    "cannot-edit-post": "This post cannot be edited",
+    "default": "This page could not be found",
+    "not-authorized": "Not authorized to this page"
   }
 }
 

webapp/middleware/isAdmin.js

@@ -1,5 +1,5 @@
 export default ({ store, error }) => {
   if (!store.getters['auth/isAdmin']) {
-    return error({ statusCode: 403 })
+    return error({ statusCode: 403, message: 'error-pages.not-authorized' })
   }
 }

webapp/middleware/isModerator.js

@@ -1,5 +1,5 @@
 export default ({ store, error }) => {
   if (!store.getters['auth/isModerator']) {
-    return error({ statusCode: 403 })
+    return error({ statusCode: 403, message: 'error-pages.not-authorized' })
   }
 }