(auth) error about broken apple auth

locale/_base/translations.suml

@@ -579,6 +579,8 @@ user:
         brokenNotice: >
             We're having technical problems with the authentication method…
             If it doesn't work for you, please log in with email (or another method).
+        oauthError: >
+            An error occurred when trying to authenticate… Please try again or use a different authentication method.
     code:
         action: 'Validate'
         invalid: 'Invalid code.'

locale/en/translations.suml

@@ -755,6 +755,8 @@ user:
         brokenNotice: >
             We're having technical problems with the authentication method…
             If it doesn't work for you, please log in with email (or another method).
+        oauthError: >
+            An error occurred when trying to authenticate… Please try again or use a different authentication method.
     code:
         action: 'Validate'
         invalid: 'Invalid code.'

pages/index.vue

@@ -1,6 +1,14 @@
 <template>
-    <Homepage v-if="$config.header" />
-    <SelectVersion v-else />
+    <div>
+        <div v-if="$route.query.error" class="container pt-md-4">
+            <div class="alert alert-danger">
+                <Icon v="heart-broken"/>
+                <T>user.login.oauthError</T>
+            </div>
+        </div>
+        <Homepage v-if="$config.header" />
+        <SelectVersion v-else />
+    </div>
 </template>
 
 <script>