diff --git a/Riot/Assets/en.lproj/Vector.strings b/Riot/Assets/en.lproj/Vector.strings
index ff69f3f29..d1677e9dd 100644
--- a/Riot/Assets/en.lproj/Vector.strings
+++ b/Riot/Assets/en.lproj/Vector.strings
@@ -48,6 +48,7 @@
 "active_call_details" = "Active Call (%@)";
 "later" = "Later";
 "rename" = "Rename";
+"collapse" = "collapse";
 
 // Authentication
 "auth_login" = "Log in";
@@ -430,6 +431,9 @@
 "directory_server_type_homeserver" = "Type a homeserver to list public rooms from";
 "directory_server_placeholder" = "matrix.org";
 
+// Events formatter
+"event_formatter_member_updates" = "%tu member updates";
+
 // Others
 "or" = "or";
 "you" = "You";
diff --git a/Riot/Utils/EventFormatter.m b/Riot/Utils/EventFormatter.m
index 236b9c8a5..4e0db0a2c 100644
--- a/Riot/Utils/EventFormatter.m
+++ b/Riot/Utils/EventFormatter.m
@@ -45,8 +45,7 @@
         {
             // This is a serie for cells tagged with RoomBubbleCellDataTagMembership
             // TODO: Build a complete summary like Riot-web
-            // TODO: i18n the temp string
-            displayText = [NSString stringWithFormat:@"%@ membership changes", @(events.count)];
+            displayText = [NSString stringWithFormat:NSLocalizedStringFromTable(@"event_formatter_member_updates", @"Vector", nil), events.count];
         }
     }