diff --git a/lib/notifications/display.dart b/lib/notifications/display.dart
index b897530c21..1b85ccaebc 100644
--- a/lib/notifications/display.dart
+++ b/lib/notifications/display.dart
@@ -25,10 +25,11 @@ import '../widgets/theme.dart';
 AndroidNotificationHostApi get _androidHost => ZulipBinding.instance.androidNotificationHost;
 
 enum NotificationSound {
-  // Any new entry here must appear in `keep.xml` too, see #528.
+  // TODO(i18n): translate these file display names
   chime2(resourceName: 'chime2', fileDisplayName: 'Zulip - Low Chime.m4a'),
   chime3(resourceName: 'chime3', fileDisplayName: 'Zulip - Chime.m4a'),
   chime4(resourceName: 'chime4', fileDisplayName: 'Zulip - High Chime.m4a');
+  // Any new entry here must appear in `keep.xml` too, see #528.
 
   const NotificationSound({
     required this.resourceName,
diff --git a/lib/widgets/content.dart b/lib/widgets/content.dart
index 02c4f05ca3..8799e8d192 100644
--- a/lib/widgets/content.dart
+++ b/lib/widgets/content.dart
@@ -1214,7 +1214,7 @@ class GlobalTime extends StatelessWidget {
   final GlobalTimeNode node;
   final TextStyle ambientTextStyle;
 
-  static final _dateFormat = DateFormat('EEE, MMM d, y, h:mm a'); // TODO(intl): localize date
+  static final _dateFormat = DateFormat('EEE, MMM d, y, h:mm a'); // TODO(i18n): localize date
 
   @override
   Widget build(BuildContext context) {
diff --git a/lib/widgets/lightbox.dart b/lib/widgets/lightbox.dart
index 1406b5fdbd..65d013a4b6 100644
--- a/lib/widgets/lightbox.dart
+++ b/lib/widgets/lightbox.dart
@@ -340,7 +340,7 @@ class VideoDurationLabel extends StatelessWidget {
     final hours = value.inHours.toString().padLeft(2, '0');
     final minutes = value.inMinutes.remainder(60).toString().padLeft(2, '0');
     final seconds = value.inSeconds.remainder(60).toString().padLeft(2, '0');
-    return '${hours == '00' ? '' : '$hours:'}$minutes:$seconds';
+    return '${hours == '00' ? '' : '$hours:'}$minutes:$seconds'; // TODO(i18n)
   }
 
   @override
diff --git a/lib/widgets/message_list.dart b/lib/widgets/message_list.dart
index 0d1a936dff..a27a8051e9 100644
--- a/lib/widgets/message_list.dart
+++ b/lib/widgets/message_list.dart
@@ -1410,5 +1410,5 @@ class MessageWithPossibleSender extends StatelessWidget {
   }
 }
 
-// TODO web seems to ignore locale in formatting time, but we could do better
+// TODO(i18n): web seems to ignore locale in formatting time, but we could do better
 final _kMessageTimestampFormat = DateFormat('h:mm aa', 'en_US');
diff --git a/lib/widgets/profile.dart b/lib/widgets/profile.dart
index f38daf792d..c4f8970ff0 100644
--- a/lib/widgets/profile.dart
+++ b/lib/widgets/profile.dart
@@ -200,7 +200,7 @@ class _ProfileDataTable extends StatelessWidget {
         // TODO(server): The value's format is undocumented, but empirically
         //   it's a date in ISO format, like 2000-01-01.
         // That's readable as is, but:
-        // TODO format this date using user's locale.
+        // TODO(i18n) format this date using user's locale.
         return _TextWidget(text: value);
 
       case CustomProfileFieldType.shortText: