fix vue warnings

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

js/src/views/Group/Group.vue

@@ -31,7 +31,11 @@
         {{ $t("You have been removed from this group's members.") }}
       </b-message>
       <b-message
-        v-if="isCurrentActorAGroupMember && isCurrentActorARecentMember"
+        v-if="
+          isCurrentActorAGroupMember &&
+          isCurrentActorARecentMember &&
+          isCurrentActorOnADifferentDomainThanGroup
+        "
         type="is-info"
       >
         {{
@@ -735,6 +739,10 @@ export default class Group extends mixins(GroupMixin) {
     );
   }
 
+  get isCurrentActorOnADifferentDomainThanGroup(): boolean {
+    return this.group.domain !== null;
+  }
+
   get members(): IMember[] {
     return this.group.members.elements.filter(
       (member) =>