diff --git a/assets/l10n/app_en.arb b/assets/l10n/app_en.arb
index 1060027553..ee7e96c35f 100644
--- a/assets/l10n/app_en.arb
+++ b/assets/l10n/app_en.arb
@@ -56,6 +56,10 @@
   "@profileButtonSendDirectMessage": {
     "description": "Label for button in profile screen to navigate to DMs with the shown user."
   },
+  "errorCouldNotShowUserProfile": "Could not show user profile.",
+  "@errorCouldNotShowUserProfile": {
+    "description": "Message that appears on the user profile page when the profile cannot be shown."
+  },
   "permissionsNeededTitle": "Permissions needed",
   "@permissionsNeededTitle": {
     "description": "Title for dialog asking the user to grant additional permissions."
@@ -230,6 +234,17 @@
       "event": {"type": "String", "example": "UpdateMessageEvent(id: 123, messageIds: [2345, 3456], newTopic: 'dinner')"}
     }
   },
+  "errorCouldNotOpenLinkTitle": "Unable to open link",
+  "@errorCouldNotOpenLinkTitle": {
+    "description": "Error title when opening a link failed."
+  },
+  "errorCouldNotOpenLink": "Link could not be opened: {url}",
+  "@errorCouldNotOpenLink": {
+    "description": "Error message when opening a link failed.",
+    "placeholders": {
+      "url": {"type":  "String", "example":  "https://chat.example.com"}
+    }
+  },
   "errorMuteTopicFailed": "Failed to mute topic",
   "@errorMuteTopicFailed": {
     "description": "Error message when muting a topic failed."
@@ -321,8 +336,8 @@
   "@composeBoxSendTooltip":  {
     "description": "Tooltip for send button in compose box."
   },
-  "composeBoxUnknownChannelName": "(unknown channel)",
-  "@composeBoxUnknownChannelName": {
+  "unknownChannelName": "(unknown channel)",
+  "@unknownChannelName": {
     "description": "Replacement name for channel when it cannot be found in the store."
   },
   "composeBoxTopicHintText": "Topic",
@@ -336,10 +351,21 @@
       "filename": {"type": "String", "example": "file.txt"}
     }
   },
+  "composeBoxLoadingMessage": "(loading message {messageId})",
+  "@composeBoxLoadingMessage": {
+    "description": "Placeholder in compose box showing the quoted message is currently loading.",
+    "placeholders": {
+      "messageId": {"type": "int", "example": "1234"}
+    }
+  },
   "unknownUserName": "(unknown user)",
   "@unknownUserName": {
     "description": "Name placeholder to use for a user when we don't know their name."
   },
+  "dmsWithYourselfPageTitle": "DMs with yourself",
+  "@dmsWithYourselfPageTitle": {
+    "description": "Message list page title for a DM group that only includes yourself."
+  },
   "messageListGroupYouAndOthers": "You and {others}",
   "@messageListGroupYouAndOthers": {
     "description": "Message list recipient header for a DM group with others.",
@@ -347,6 +373,13 @@
       "others": {"type": "String", "example": "Alice, Bob"}
     }
   },
+  "dmsWithOthersPageTitle": "DMs with {others}",
+  "@dmsWithOthersPageTitle": {
+    "description": "Message list page title for a DM group with others.",
+    "placeholders": {
+      "others": {"type": "String", "example": "Alice, Bob"}
+    }
+  },
   "messageListGroupYouWithYourself": "You with yourself",
   "@messageListGroupYouWithYourself": {
     "description": "Message list recipient header for a DM group that only includes yourself."
@@ -395,6 +428,14 @@
   "@lightboxCopyLinkTooltip": {
     "description": "Tooltip in lightbox for the copy link action."
   },
+  "lightboxVideoCurrentPosition": "Current position",
+  "@lightboxVideoCurrentPosition": {
+    "description": "The current playback position of the video playing in the lightbox."
+  },
+  "lightboxVideoDuration": "Video duration",
+  "@lightboxVideoDuration": {
+    "description": "The total duration of the video playing in the lightbox."
+  },
   "loginPageTitle": "Log in",
   "@loginPageTitle": {
     "description": "Title for login page."
@@ -586,6 +627,10 @@
   "@recentDmConversationsPageTitle": {
     "description": "Title for the page with a list of DM conversations."
   },
+  "recentDmConversationsSectionHeader": "Direct messages",
+  "@recentDmConversationsSectionHeader": {
+    "description": "Heading for direct messages section on the 'Inbox' message view."
+  },
   "combinedFeedPageTitle": "Combined feed",
   "@combinedFeedPageTitle": {
     "description": "Page title for the 'Combined feed' message view."
@@ -618,10 +663,26 @@
       "numOthers": {"type": "int", "example": "4"}
     }
   },
+  "pinnedSubscriptionsLabel": "Pinned",
+  "@pinnedSubscriptionsLabel": {
+    "description": "Label for the list of pinned subscribed channels."
+  },
+  "unpinnedSubscriptionsLabel": "Unpinned",
+  "@unpinnedSubscriptionsLabel": {
+    "description": "Label for the list of unpinned subscribed channels."
+  },
+  "subscriptionListNoChannels": "No channels found",
+  "@subscriptionListNoChannels": {
+    "description": "Text to display on subscribed-channels page when there are no subscribed channels."
+  },
   "notifSelfUser": "You",
   "@notifSelfUser": {
     "description": "Display name for the user themself, to show after replying in an Android notification"
   },
+  "reactedEmojiSelfUser": "You",
+  "@reactedEmojiSelfUser": {
+    "description": "Display name for the user themself, to show on an emoji reaction added by the user."
+  },
   "onePersonTyping": "{typist} is typing…",
   "@onePersonTyping": {
     "description": "Text to display when there is one user typing.",
@@ -685,6 +746,13 @@
   "@messageIsMovedLabel": {
     "description": "Label for a moved message. (Use ALL CAPS for cased alphabets: Latin, Greek, Cyrillic, etc.)"
   },
+  "pollVoterNames": "({voterNames})",
+  "@pollVoterNames": {
+    "description": "The list of people who voted for a poll option, wrapped in parentheses.",
+    "placeholders": {
+      "voterNames": {"type":  "String", "example": "Alice, Bob, Chad"}
+    }
+  },
   "pollWidgetQuestionMissing": "No question.",
   "@pollWidgetQuestionMissing": {
     "description": "Text to display for a poll when the question is missing"
@@ -716,5 +784,13 @@
   "emojiPickerSearchEmoji": "Search emoji",
   "@emojiPickerSearchEmoji": {
     "description": "Hint text for the emoji picker search text field."
+  },
+  "noEarlierMessages": "No earlier messages",
+  "@noEarlierMessages": {
+    "description": "Text to show at the start of a message list if there are no earlier messages."
+  },
+  "scrollToBottomTooltip": "Scroll to bottom",
+  "@scrollToBottomTooltip": {
+    "description": "Tooltip for button to scroll to bottom."
   }
 }
diff --git a/lib/generated/l10n/zulip_localizations.dart b/lib/generated/l10n/zulip_localizations.dart
index 501eb577bf..b6fbb70769 100644
--- a/lib/generated/l10n/zulip_localizations.dart
+++ b/lib/generated/l10n/zulip_localizations.dart
@@ -189,6 +189,12 @@ abstract class ZulipLocalizations {
   /// **'Send direct message'**
   String get profileButtonSendDirectMessage;
 
+  /// Message that appears on the user profile page when the profile cannot be shown.
+  ///
+  /// In en, this message translates to:
+  /// **'Could not show user profile.'**
+  String get errorCouldNotShowUserProfile;
+
   /// Title for dialog asking the user to grant additional permissions.
   ///
   /// In en, this message translates to:
@@ -405,6 +411,18 @@ abstract class ZulipLocalizations {
   /// **'Error handling a Zulip event from {serverUrl}; will retry.\n\nError: {error}\n\nEvent: {event}'**
   String errorHandlingEventDetails(String serverUrl, String error, String event);
 
+  /// Error title when opening a link failed.
+  ///
+  /// In en, this message translates to:
+  /// **'Unable to open link'**
+  String get errorCouldNotOpenLinkTitle;
+
+  /// Error message when opening a link failed.
+  ///
+  /// In en, this message translates to:
+  /// **'Link could not be opened: {url}'**
+  String errorCouldNotOpenLink(String url);
+
   /// Error message when muting a topic failed.
   ///
   /// In en, this message translates to:
@@ -535,7 +553,7 @@ abstract class ZulipLocalizations {
   ///
   /// In en, this message translates to:
   /// **'(unknown channel)'**
-  String get composeBoxUnknownChannelName;
+  String get unknownChannelName;
 
   /// Hint text for topic input widget in compose box.
   ///
@@ -549,18 +567,36 @@ abstract class ZulipLocalizations {
   /// **'Uploading {filename}…'**
   String composeBoxUploadingFilename(String filename);
 
+  /// Placeholder in compose box showing the quoted message is currently loading.
+  ///
+  /// In en, this message translates to:
+  /// **'(loading message {messageId})'**
+  String composeBoxLoadingMessage(int messageId);
+
   /// Name placeholder to use for a user when we don't know their name.
   ///
   /// In en, this message translates to:
   /// **'(unknown user)'**
   String get unknownUserName;
 
+  /// Message list page title for a DM group that only includes yourself.
+  ///
+  /// In en, this message translates to:
+  /// **'DMs with yourself'**
+  String get dmsWithYourselfPageTitle;
+
   /// Message list recipient header for a DM group with others.
   ///
   /// In en, this message translates to:
   /// **'You and {others}'**
   String messageListGroupYouAndOthers(String others);
 
+  /// Message list page title for a DM group with others.
+  ///
+  /// In en, this message translates to:
+  /// **'DMs with {others}'**
+  String dmsWithOthersPageTitle(String others);
+
   /// Message list recipient header for a DM group that only includes yourself.
   ///
   /// In en, this message translates to:
@@ -633,6 +669,18 @@ abstract class ZulipLocalizations {
   /// **'Copy link'**
   String get lightboxCopyLinkTooltip;
 
+  /// The current playback position of the video playing in the lightbox.
+  ///
+  /// In en, this message translates to:
+  /// **'Current position'**
+  String get lightboxVideoCurrentPosition;
+
+  /// The total duration of the video playing in the lightbox.
+  ///
+  /// In en, this message translates to:
+  /// **'Video duration'**
+  String get lightboxVideoDuration;
+
   /// Title for login page.
   ///
   /// In en, this message translates to:
@@ -891,6 +939,12 @@ abstract class ZulipLocalizations {
   /// **'Direct messages'**
   String get recentDmConversationsPageTitle;
 
+  /// Heading for direct messages section on the 'Inbox' message view.
+  ///
+  /// In en, this message translates to:
+  /// **'Direct messages'**
+  String get recentDmConversationsSectionHeader;
+
   /// Page title for the 'Combined feed' message view.
   ///
   /// In en, this message translates to:
@@ -933,12 +987,36 @@ abstract class ZulipLocalizations {
   /// **'{senderFullName} to you and {numOthers, plural, =1{1 other} other{{numOthers} others}}'**
   String notifGroupDmConversationLabel(String senderFullName, int numOthers);
 
+  /// Label for the list of pinned subscribed channels.
+  ///
+  /// In en, this message translates to:
+  /// **'Pinned'**
+  String get pinnedSubscriptionsLabel;
+
+  /// Label for the list of unpinned subscribed channels.
+  ///
+  /// In en, this message translates to:
+  /// **'Unpinned'**
+  String get unpinnedSubscriptionsLabel;
+
+  /// Text to display on subscribed-channels page when there are no subscribed channels.
+  ///
+  /// In en, this message translates to:
+  /// **'No channels found'**
+  String get subscriptionListNoChannels;
+
   /// Display name for the user themself, to show after replying in an Android notification
   ///
   /// In en, this message translates to:
   /// **'You'**
   String get notifSelfUser;
 
+  /// Display name for the user themself, to show on an emoji reaction added by the user.
+  ///
+  /// In en, this message translates to:
+  /// **'You'**
+  String get reactedEmojiSelfUser;
+
   /// Text to display when there is one user typing.
   ///
   /// In en, this message translates to:
@@ -1023,6 +1101,12 @@ abstract class ZulipLocalizations {
   /// **'MOVED'**
   String get messageIsMovedLabel;
 
+  /// The list of people who voted for a poll option, wrapped in parentheses.
+  ///
+  /// In en, this message translates to:
+  /// **'({voterNames})'**
+  String pollVoterNames(String voterNames);
+
   /// Text to display for a poll when the question is missing
   ///
   /// In en, this message translates to:
@@ -1070,6 +1154,18 @@ abstract class ZulipLocalizations {
   /// In en, this message translates to:
   /// **'Search emoji'**
   String get emojiPickerSearchEmoji;
+
+  /// Text to show at the start of a message list if there are no earlier messages.
+  ///
+  /// In en, this message translates to:
+  /// **'No earlier messages'**
+  String get noEarlierMessages;
+
+  /// Tooltip for button to scroll to bottom.
+  ///
+  /// In en, this message translates to:
+  /// **'Scroll to bottom'**
+  String get scrollToBottomTooltip;
 }
 
 class _ZulipLocalizationsDelegate extends LocalizationsDelegate<ZulipLocalizations> {
diff --git a/lib/generated/l10n/zulip_localizations_ar.dart b/lib/generated/l10n/zulip_localizations_ar.dart
index 721b20ac02..025b4b1444 100644
--- a/lib/generated/l10n/zulip_localizations_ar.dart
+++ b/lib/generated/l10n/zulip_localizations_ar.dart
@@ -52,6 +52,9 @@ class ZulipLocalizationsAr extends ZulipLocalizations {
   @override
   String get profileButtonSendDirectMessage => 'Send direct message';
 
+  @override
+  String get errorCouldNotShowUserProfile => 'Could not show user profile.';
+
   @override
   String get permissionsNeededTitle => 'Permissions needed';
 
@@ -188,6 +191,14 @@ class ZulipLocalizationsAr extends ZulipLocalizations {
     return 'Error handling a Zulip event from $serverUrl; will retry.\n\nError: $error\n\nEvent: $event';
   }
 
+  @override
+  String get errorCouldNotOpenLinkTitle => 'Unable to open link';
+
+  @override
+  String errorCouldNotOpenLink(String url) {
+    return 'Link could not be opened: $url';
+  }
+
   @override
   String get errorMuteTopicFailed => 'Failed to mute topic';
 
@@ -256,7 +267,7 @@ class ZulipLocalizationsAr extends ZulipLocalizations {
   String get composeBoxSendTooltip => 'Send';
 
   @override
-  String get composeBoxUnknownChannelName => '(unknown channel)';
+  String get unknownChannelName => '(unknown channel)';
 
   @override
   String get composeBoxTopicHintText => 'Topic';
@@ -266,14 +277,27 @@ class ZulipLocalizationsAr extends ZulipLocalizations {
     return 'Uploading $filename…';
   }
 
+  @override
+  String composeBoxLoadingMessage(int messageId) {
+    return '(loading message $messageId)';
+  }
+
   @override
   String get unknownUserName => '(unknown user)';
 
+  @override
+  String get dmsWithYourselfPageTitle => 'DMs with yourself';
+
   @override
   String messageListGroupYouAndOthers(String others) {
     return 'You and $others';
   }
 
+  @override
+  String dmsWithOthersPageTitle(String others) {
+    return 'DMs with $others';
+  }
+
   @override
   String get messageListGroupYouWithYourself => 'You with yourself';
 
@@ -310,6 +334,12 @@ class ZulipLocalizationsAr extends ZulipLocalizations {
   @override
   String get lightboxCopyLinkTooltip => 'Copy link';
 
+  @override
+  String get lightboxVideoCurrentPosition => 'Current position';
+
+  @override
+  String get lightboxVideoDuration => 'Video duration';
+
   @override
   String get loginPageTitle => 'Log in';
 
@@ -463,6 +493,9 @@ class ZulipLocalizationsAr extends ZulipLocalizations {
   @override
   String get recentDmConversationsPageTitle => 'Direct messages';
 
+  @override
+  String get recentDmConversationsSectionHeader => 'Direct messages';
+
   @override
   String get combinedFeedPageTitle => 'Combined feed';
 
@@ -492,9 +525,21 @@ class ZulipLocalizationsAr extends ZulipLocalizations {
     return '$senderFullName to you and $_temp0';
   }
 
+  @override
+  String get pinnedSubscriptionsLabel => 'Pinned';
+
+  @override
+  String get unpinnedSubscriptionsLabel => 'Unpinned';
+
+  @override
+  String get subscriptionListNoChannels => 'No channels found';
+
   @override
   String get notifSelfUser => 'You';
 
+  @override
+  String get reactedEmojiSelfUser => 'You';
+
   @override
   String onePersonTyping(String typist) {
     return '$typist is typing…';
@@ -541,6 +586,11 @@ class ZulipLocalizationsAr extends ZulipLocalizations {
   @override
   String get messageIsMovedLabel => 'MOVED';
 
+  @override
+  String pollVoterNames(String voterNames) {
+    return '($voterNames)';
+  }
+
   @override
   String get pollWidgetQuestionMissing => 'No question.';
 
@@ -564,4 +614,10 @@ class ZulipLocalizationsAr extends ZulipLocalizations {
 
   @override
   String get emojiPickerSearchEmoji => 'Search emoji';
+
+  @override
+  String get noEarlierMessages => 'No earlier messages';
+
+  @override
+  String get scrollToBottomTooltip => 'Scroll to bottom';
 }
diff --git a/lib/generated/l10n/zulip_localizations_en.dart b/lib/generated/l10n/zulip_localizations_en.dart
index 6936cfe736..9467d33428 100644
--- a/lib/generated/l10n/zulip_localizations_en.dart
+++ b/lib/generated/l10n/zulip_localizations_en.dart
@@ -52,6 +52,9 @@ class ZulipLocalizationsEn extends ZulipLocalizations {
   @override
   String get profileButtonSendDirectMessage => 'Send direct message';
 
+  @override
+  String get errorCouldNotShowUserProfile => 'Could not show user profile.';
+
   @override
   String get permissionsNeededTitle => 'Permissions needed';
 
@@ -188,6 +191,14 @@ class ZulipLocalizationsEn extends ZulipLocalizations {
     return 'Error handling a Zulip event from $serverUrl; will retry.\n\nError: $error\n\nEvent: $event';
   }
 
+  @override
+  String get errorCouldNotOpenLinkTitle => 'Unable to open link';
+
+  @override
+  String errorCouldNotOpenLink(String url) {
+    return 'Link could not be opened: $url';
+  }
+
   @override
   String get errorMuteTopicFailed => 'Failed to mute topic';
 
@@ -256,7 +267,7 @@ class ZulipLocalizationsEn extends ZulipLocalizations {
   String get composeBoxSendTooltip => 'Send';
 
   @override
-  String get composeBoxUnknownChannelName => '(unknown channel)';
+  String get unknownChannelName => '(unknown channel)';
 
   @override
   String get composeBoxTopicHintText => 'Topic';
@@ -266,14 +277,27 @@ class ZulipLocalizationsEn extends ZulipLocalizations {
     return 'Uploading $filename…';
   }
 
+  @override
+  String composeBoxLoadingMessage(int messageId) {
+    return '(loading message $messageId)';
+  }
+
   @override
   String get unknownUserName => '(unknown user)';
 
+  @override
+  String get dmsWithYourselfPageTitle => 'DMs with yourself';
+
   @override
   String messageListGroupYouAndOthers(String others) {
     return 'You and $others';
   }
 
+  @override
+  String dmsWithOthersPageTitle(String others) {
+    return 'DMs with $others';
+  }
+
   @override
   String get messageListGroupYouWithYourself => 'You with yourself';
 
@@ -310,6 +334,12 @@ class ZulipLocalizationsEn extends ZulipLocalizations {
   @override
   String get lightboxCopyLinkTooltip => 'Copy link';
 
+  @override
+  String get lightboxVideoCurrentPosition => 'Current position';
+
+  @override
+  String get lightboxVideoDuration => 'Video duration';
+
   @override
   String get loginPageTitle => 'Log in';
 
@@ -463,6 +493,9 @@ class ZulipLocalizationsEn extends ZulipLocalizations {
   @override
   String get recentDmConversationsPageTitle => 'Direct messages';
 
+  @override
+  String get recentDmConversationsSectionHeader => 'Direct messages';
+
   @override
   String get combinedFeedPageTitle => 'Combined feed';
 
@@ -492,9 +525,21 @@ class ZulipLocalizationsEn extends ZulipLocalizations {
     return '$senderFullName to you and $_temp0';
   }
 
+  @override
+  String get pinnedSubscriptionsLabel => 'Pinned';
+
+  @override
+  String get unpinnedSubscriptionsLabel => 'Unpinned';
+
+  @override
+  String get subscriptionListNoChannels => 'No channels found';
+
   @override
   String get notifSelfUser => 'You';
 
+  @override
+  String get reactedEmojiSelfUser => 'You';
+
   @override
   String onePersonTyping(String typist) {
     return '$typist is typing…';
@@ -541,6 +586,11 @@ class ZulipLocalizationsEn extends ZulipLocalizations {
   @override
   String get messageIsMovedLabel => 'MOVED';
 
+  @override
+  String pollVoterNames(String voterNames) {
+    return '($voterNames)';
+  }
+
   @override
   String get pollWidgetQuestionMissing => 'No question.';
 
@@ -564,4 +614,10 @@ class ZulipLocalizationsEn extends ZulipLocalizations {
 
   @override
   String get emojiPickerSearchEmoji => 'Search emoji';
+
+  @override
+  String get noEarlierMessages => 'No earlier messages';
+
+  @override
+  String get scrollToBottomTooltip => 'Scroll to bottom';
 }
diff --git a/lib/generated/l10n/zulip_localizations_ja.dart b/lib/generated/l10n/zulip_localizations_ja.dart
index c431471645..f363ee0043 100644
--- a/lib/generated/l10n/zulip_localizations_ja.dart
+++ b/lib/generated/l10n/zulip_localizations_ja.dart
@@ -52,6 +52,9 @@ class ZulipLocalizationsJa extends ZulipLocalizations {
   @override
   String get profileButtonSendDirectMessage => 'ダイレクトメッセージを送信';
 
+  @override
+  String get errorCouldNotShowUserProfile => 'Could not show user profile.';
+
   @override
   String get permissionsNeededTitle => 'Permissions needed';
 
@@ -188,6 +191,14 @@ class ZulipLocalizationsJa extends ZulipLocalizations {
     return 'Error handling a Zulip event from $serverUrl; will retry.\n\nError: $error\n\nEvent: $event';
   }
 
+  @override
+  String get errorCouldNotOpenLinkTitle => 'Unable to open link';
+
+  @override
+  String errorCouldNotOpenLink(String url) {
+    return 'Link could not be opened: $url';
+  }
+
   @override
   String get errorMuteTopicFailed => 'Failed to mute topic';
 
@@ -256,7 +267,7 @@ class ZulipLocalizationsJa extends ZulipLocalizations {
   String get composeBoxSendTooltip => 'Send';
 
   @override
-  String get composeBoxUnknownChannelName => '(unknown channel)';
+  String get unknownChannelName => '(unknown channel)';
 
   @override
   String get composeBoxTopicHintText => 'Topic';
@@ -266,14 +277,27 @@ class ZulipLocalizationsJa extends ZulipLocalizations {
     return 'Uploading $filename…';
   }
 
+  @override
+  String composeBoxLoadingMessage(int messageId) {
+    return '(loading message $messageId)';
+  }
+
   @override
   String get unknownUserName => '(unknown user)';
 
+  @override
+  String get dmsWithYourselfPageTitle => 'DMs with yourself';
+
   @override
   String messageListGroupYouAndOthers(String others) {
     return 'You and $others';
   }
 
+  @override
+  String dmsWithOthersPageTitle(String others) {
+    return 'DMs with $others';
+  }
+
   @override
   String get messageListGroupYouWithYourself => 'You with yourself';
 
@@ -310,6 +334,12 @@ class ZulipLocalizationsJa extends ZulipLocalizations {
   @override
   String get lightboxCopyLinkTooltip => 'Copy link';
 
+  @override
+  String get lightboxVideoCurrentPosition => 'Current position';
+
+  @override
+  String get lightboxVideoDuration => 'Video duration';
+
   @override
   String get loginPageTitle => 'Log in';
 
@@ -463,6 +493,9 @@ class ZulipLocalizationsJa extends ZulipLocalizations {
   @override
   String get recentDmConversationsPageTitle => 'Direct messages';
 
+  @override
+  String get recentDmConversationsSectionHeader => 'Direct messages';
+
   @override
   String get combinedFeedPageTitle => 'Combined feed';
 
@@ -492,9 +525,21 @@ class ZulipLocalizationsJa extends ZulipLocalizations {
     return '$senderFullName to you and $_temp0';
   }
 
+  @override
+  String get pinnedSubscriptionsLabel => 'Pinned';
+
+  @override
+  String get unpinnedSubscriptionsLabel => 'Unpinned';
+
+  @override
+  String get subscriptionListNoChannels => 'No channels found';
+
   @override
   String get notifSelfUser => 'You';
 
+  @override
+  String get reactedEmojiSelfUser => 'You';
+
   @override
   String onePersonTyping(String typist) {
     return '$typist is typing…';
@@ -541,6 +586,11 @@ class ZulipLocalizationsJa extends ZulipLocalizations {
   @override
   String get messageIsMovedLabel => 'MOVED';
 
+  @override
+  String pollVoterNames(String voterNames) {
+    return '($voterNames)';
+  }
+
   @override
   String get pollWidgetQuestionMissing => 'No question.';
 
@@ -564,4 +614,10 @@ class ZulipLocalizationsJa extends ZulipLocalizations {
 
   @override
   String get emojiPickerSearchEmoji => 'Search emoji';
+
+  @override
+  String get noEarlierMessages => 'No earlier messages';
+
+  @override
+  String get scrollToBottomTooltip => 'Scroll to bottom';
 }
diff --git a/lib/generated/l10n/zulip_localizations_nb.dart b/lib/generated/l10n/zulip_localizations_nb.dart
index fc530fccaa..35b3e86fe5 100644
--- a/lib/generated/l10n/zulip_localizations_nb.dart
+++ b/lib/generated/l10n/zulip_localizations_nb.dart
@@ -52,6 +52,9 @@ class ZulipLocalizationsNb extends ZulipLocalizations {
   @override
   String get profileButtonSendDirectMessage => 'Send direct message';
 
+  @override
+  String get errorCouldNotShowUserProfile => 'Could not show user profile.';
+
   @override
   String get permissionsNeededTitle => 'Permissions needed';
 
@@ -188,6 +191,14 @@ class ZulipLocalizationsNb extends ZulipLocalizations {
     return 'Error handling a Zulip event from $serverUrl; will retry.\n\nError: $error\n\nEvent: $event';
   }
 
+  @override
+  String get errorCouldNotOpenLinkTitle => 'Unable to open link';
+
+  @override
+  String errorCouldNotOpenLink(String url) {
+    return 'Link could not be opened: $url';
+  }
+
   @override
   String get errorMuteTopicFailed => 'Failed to mute topic';
 
@@ -256,7 +267,7 @@ class ZulipLocalizationsNb extends ZulipLocalizations {
   String get composeBoxSendTooltip => 'Send';
 
   @override
-  String get composeBoxUnknownChannelName => '(unknown channel)';
+  String get unknownChannelName => '(unknown channel)';
 
   @override
   String get composeBoxTopicHintText => 'Topic';
@@ -266,14 +277,27 @@ class ZulipLocalizationsNb extends ZulipLocalizations {
     return 'Uploading $filename…';
   }
 
+  @override
+  String composeBoxLoadingMessage(int messageId) {
+    return '(loading message $messageId)';
+  }
+
   @override
   String get unknownUserName => '(unknown user)';
 
+  @override
+  String get dmsWithYourselfPageTitle => 'DMs with yourself';
+
   @override
   String messageListGroupYouAndOthers(String others) {
     return 'You and $others';
   }
 
+  @override
+  String dmsWithOthersPageTitle(String others) {
+    return 'DMs with $others';
+  }
+
   @override
   String get messageListGroupYouWithYourself => 'You with yourself';
 
@@ -310,6 +334,12 @@ class ZulipLocalizationsNb extends ZulipLocalizations {
   @override
   String get lightboxCopyLinkTooltip => 'Copy link';
 
+  @override
+  String get lightboxVideoCurrentPosition => 'Current position';
+
+  @override
+  String get lightboxVideoDuration => 'Video duration';
+
   @override
   String get loginPageTitle => 'Log in';
 
@@ -463,6 +493,9 @@ class ZulipLocalizationsNb extends ZulipLocalizations {
   @override
   String get recentDmConversationsPageTitle => 'Direct messages';
 
+  @override
+  String get recentDmConversationsSectionHeader => 'Direct messages';
+
   @override
   String get combinedFeedPageTitle => 'Combined feed';
 
@@ -492,9 +525,21 @@ class ZulipLocalizationsNb extends ZulipLocalizations {
     return '$senderFullName to you and $_temp0';
   }
 
+  @override
+  String get pinnedSubscriptionsLabel => 'Pinned';
+
+  @override
+  String get unpinnedSubscriptionsLabel => 'Unpinned';
+
+  @override
+  String get subscriptionListNoChannels => 'No channels found';
+
   @override
   String get notifSelfUser => 'You';
 
+  @override
+  String get reactedEmojiSelfUser => 'You';
+
   @override
   String onePersonTyping(String typist) {
     return '$typist is typing…';
@@ -541,6 +586,11 @@ class ZulipLocalizationsNb extends ZulipLocalizations {
   @override
   String get messageIsMovedLabel => 'MOVED';
 
+  @override
+  String pollVoterNames(String voterNames) {
+    return '($voterNames)';
+  }
+
   @override
   String get pollWidgetQuestionMissing => 'No question.';
 
@@ -564,4 +614,10 @@ class ZulipLocalizationsNb extends ZulipLocalizations {
 
   @override
   String get emojiPickerSearchEmoji => 'Search emoji';
+
+  @override
+  String get noEarlierMessages => 'No earlier messages';
+
+  @override
+  String get scrollToBottomTooltip => 'Scroll to bottom';
 }
diff --git a/lib/generated/l10n/zulip_localizations_pl.dart b/lib/generated/l10n/zulip_localizations_pl.dart
index f817d400a8..0594722d31 100644
--- a/lib/generated/l10n/zulip_localizations_pl.dart
+++ b/lib/generated/l10n/zulip_localizations_pl.dart
@@ -52,6 +52,9 @@ class ZulipLocalizationsPl extends ZulipLocalizations {
   @override
   String get profileButtonSendDirectMessage => 'Wyślij wiadomość bezpośrednią';
 
+  @override
+  String get errorCouldNotShowUserProfile => 'Could not show user profile.';
+
   @override
   String get permissionsNeededTitle => 'Wymagane uprawnienia';
 
@@ -188,6 +191,14 @@ class ZulipLocalizationsPl extends ZulipLocalizations {
     return 'Błąd zdarzenia Zulip z $serverUrl; ponawiam.\n\nBłąd: $error\n\nZdarzenie: $event';
   }
 
+  @override
+  String get errorCouldNotOpenLinkTitle => 'Unable to open link';
+
+  @override
+  String errorCouldNotOpenLink(String url) {
+    return 'Link could not be opened: $url';
+  }
+
   @override
   String get errorMuteTopicFailed => 'Wyciszenie bez powodzenia';
 
@@ -256,7 +267,7 @@ class ZulipLocalizationsPl extends ZulipLocalizations {
   String get composeBoxSendTooltip => 'Wyślij';
 
   @override
-  String get composeBoxUnknownChannelName => '(nieznany kanał)';
+  String get unknownChannelName => '(unknown channel)';
 
   @override
   String get composeBoxTopicHintText => 'Wątek';
@@ -266,14 +277,27 @@ class ZulipLocalizationsPl extends ZulipLocalizations {
     return 'Przekazywanie $filename…';
   }
 
+  @override
+  String composeBoxLoadingMessage(int messageId) {
+    return '(loading message $messageId)';
+  }
+
   @override
   String get unknownUserName => '(nieznany użytkownik)';
 
+  @override
+  String get dmsWithYourselfPageTitle => 'DMs with yourself';
+
   @override
   String messageListGroupYouAndOthers(String others) {
     return 'Ty i $others';
   }
 
+  @override
+  String dmsWithOthersPageTitle(String others) {
+    return 'DMs with $others';
+  }
+
   @override
   String get messageListGroupYouWithYourself => 'Ty ze sobą';
 
@@ -310,6 +334,12 @@ class ZulipLocalizationsPl extends ZulipLocalizations {
   @override
   String get lightboxCopyLinkTooltip => 'Skopiuj odnośnik';
 
+  @override
+  String get lightboxVideoCurrentPosition => 'Current position';
+
+  @override
+  String get lightboxVideoDuration => 'Video duration';
+
   @override
   String get loginPageTitle => 'Zaloguj';
 
@@ -463,6 +493,9 @@ class ZulipLocalizationsPl extends ZulipLocalizations {
   @override
   String get recentDmConversationsPageTitle => 'Wiadomości bezpośrednie';
 
+  @override
+  String get recentDmConversationsSectionHeader => 'Direct messages';
+
   @override
   String get combinedFeedPageTitle => 'Mieszany widok';
 
@@ -492,9 +525,21 @@ class ZulipLocalizationsPl extends ZulipLocalizations {
     return '$senderFullName do ciebie i $_temp0';
   }
 
+  @override
+  String get pinnedSubscriptionsLabel => 'Pinned';
+
+  @override
+  String get unpinnedSubscriptionsLabel => 'Unpinned';
+
+  @override
+  String get subscriptionListNoChannels => 'No channels found';
+
   @override
   String get notifSelfUser => 'Ty';
 
+  @override
+  String get reactedEmojiSelfUser => 'You';
+
   @override
   String onePersonTyping(String typist) {
     return '$typist coś pisze…';
@@ -541,6 +586,11 @@ class ZulipLocalizationsPl extends ZulipLocalizations {
   @override
   String get messageIsMovedLabel => 'PRZENIESIONO';
 
+  @override
+  String pollVoterNames(String voterNames) {
+    return '($voterNames)';
+  }
+
   @override
   String get pollWidgetQuestionMissing => 'Brak pytania.';
 
@@ -564,4 +614,10 @@ class ZulipLocalizationsPl extends ZulipLocalizations {
 
   @override
   String get emojiPickerSearchEmoji => 'Szukaj emoji';
+
+  @override
+  String get noEarlierMessages => 'No earlier messages';
+
+  @override
+  String get scrollToBottomTooltip => 'Scroll to bottom';
 }
diff --git a/lib/generated/l10n/zulip_localizations_ru.dart b/lib/generated/l10n/zulip_localizations_ru.dart
index f6d8f1e41c..879559fed4 100644
--- a/lib/generated/l10n/zulip_localizations_ru.dart
+++ b/lib/generated/l10n/zulip_localizations_ru.dart
@@ -52,6 +52,9 @@ class ZulipLocalizationsRu extends ZulipLocalizations {
   @override
   String get profileButtonSendDirectMessage => 'Отправить личное сообщение';
 
+  @override
+  String get errorCouldNotShowUserProfile => 'Could not show user profile.';
+
   @override
   String get permissionsNeededTitle => 'Требуются разрешения';
 
@@ -188,6 +191,14 @@ class ZulipLocalizationsRu extends ZulipLocalizations {
     return 'Ошибка обработки события Zulip от $serverUrl; повторим попытку.\n\nОшибка: $error\n\nСобытие: $event';
   }
 
+  @override
+  String get errorCouldNotOpenLinkTitle => 'Unable to open link';
+
+  @override
+  String errorCouldNotOpenLink(String url) {
+    return 'Link could not be opened: $url';
+  }
+
   @override
   String get errorMuteTopicFailed => 'Не удалось отключить тему';
 
@@ -256,7 +267,7 @@ class ZulipLocalizationsRu extends ZulipLocalizations {
   String get composeBoxSendTooltip => 'Отправить';
 
   @override
-  String get composeBoxUnknownChannelName => '(неизвестный канал)';
+  String get unknownChannelName => '(unknown channel)';
 
   @override
   String get composeBoxTopicHintText => 'Тема';
@@ -266,14 +277,27 @@ class ZulipLocalizationsRu extends ZulipLocalizations {
     return 'Загрузка $filename…';
   }
 
+  @override
+  String composeBoxLoadingMessage(int messageId) {
+    return '(loading message $messageId)';
+  }
+
   @override
   String get unknownUserName => '(неизвестный пользователь)';
 
+  @override
+  String get dmsWithYourselfPageTitle => 'DMs with yourself';
+
   @override
   String messageListGroupYouAndOthers(String others) {
     return 'Вы и $others';
   }
 
+  @override
+  String dmsWithOthersPageTitle(String others) {
+    return 'DMs with $others';
+  }
+
   @override
   String get messageListGroupYouWithYourself => 'Вы с собой';
 
@@ -310,6 +334,12 @@ class ZulipLocalizationsRu extends ZulipLocalizations {
   @override
   String get lightboxCopyLinkTooltip => 'Скопировать ссылку';
 
+  @override
+  String get lightboxVideoCurrentPosition => 'Current position';
+
+  @override
+  String get lightboxVideoDuration => 'Video duration';
+
   @override
   String get loginPageTitle => 'Вход в систему';
 
@@ -463,6 +493,9 @@ class ZulipLocalizationsRu extends ZulipLocalizations {
   @override
   String get recentDmConversationsPageTitle => 'Личные сообщения';
 
+  @override
+  String get recentDmConversationsSectionHeader => 'Direct messages';
+
   @override
   String get combinedFeedPageTitle => 'Объединенная лента';
 
@@ -492,9 +525,21 @@ class ZulipLocalizationsRu extends ZulipLocalizations {
     return '$senderFullName вам и еще $_temp0';
   }
 
+  @override
+  String get pinnedSubscriptionsLabel => 'Pinned';
+
+  @override
+  String get unpinnedSubscriptionsLabel => 'Unpinned';
+
+  @override
+  String get subscriptionListNoChannels => 'No channels found';
+
   @override
   String get notifSelfUser => 'Вы';
 
+  @override
+  String get reactedEmojiSelfUser => 'You';
+
   @override
   String onePersonTyping(String typist) {
     return '$typist набирает сообщение…';
@@ -541,6 +586,11 @@ class ZulipLocalizationsRu extends ZulipLocalizations {
   @override
   String get messageIsMovedLabel => 'ПЕРЕМЕЩЕНО';
 
+  @override
+  String pollVoterNames(String voterNames) {
+    return '($voterNames)';
+  }
+
   @override
   String get pollWidgetQuestionMissing => 'Нет вопроса.';
 
@@ -564,4 +614,10 @@ class ZulipLocalizationsRu extends ZulipLocalizations {
 
   @override
   String get emojiPickerSearchEmoji => 'Поиск эмодзи';
+
+  @override
+  String get noEarlierMessages => 'No earlier messages';
+
+  @override
+  String get scrollToBottomTooltip => 'Scroll to bottom';
 }
diff --git a/lib/generated/l10n/zulip_localizations_sk.dart b/lib/generated/l10n/zulip_localizations_sk.dart
index d6e04126d3..af87dfd949 100644
--- a/lib/generated/l10n/zulip_localizations_sk.dart
+++ b/lib/generated/l10n/zulip_localizations_sk.dart
@@ -52,6 +52,9 @@ class ZulipLocalizationsSk extends ZulipLocalizations {
   @override
   String get profileButtonSendDirectMessage => 'Poslať priamu správu';
 
+  @override
+  String get errorCouldNotShowUserProfile => 'Could not show user profile.';
+
   @override
   String get permissionsNeededTitle => 'Permissions needed';
 
@@ -188,6 +191,14 @@ class ZulipLocalizationsSk extends ZulipLocalizations {
     return 'Chyba obsluhy Zulip udalosti na serveri $serverUrl; skúsim znovu.\n\nChyba: $error\n\nUdalosť: $event';
   }
 
+  @override
+  String get errorCouldNotOpenLinkTitle => 'Unable to open link';
+
+  @override
+  String errorCouldNotOpenLink(String url) {
+    return 'Link could not be opened: $url';
+  }
+
   @override
   String get errorMuteTopicFailed => 'Nepodarilo sa ztíšiť tému';
 
@@ -256,7 +267,7 @@ class ZulipLocalizationsSk extends ZulipLocalizations {
   String get composeBoxSendTooltip => 'Send';
 
   @override
-  String get composeBoxUnknownChannelName => '(unknown channel)';
+  String get unknownChannelName => '(unknown channel)';
 
   @override
   String get composeBoxTopicHintText => 'Topic';
@@ -266,14 +277,27 @@ class ZulipLocalizationsSk extends ZulipLocalizations {
     return 'Uploading $filename…';
   }
 
+  @override
+  String composeBoxLoadingMessage(int messageId) {
+    return '(loading message $messageId)';
+  }
+
   @override
   String get unknownUserName => '(unknown user)';
 
+  @override
+  String get dmsWithYourselfPageTitle => 'DMs with yourself';
+
   @override
   String messageListGroupYouAndOthers(String others) {
     return 'You and $others';
   }
 
+  @override
+  String dmsWithOthersPageTitle(String others) {
+    return 'DMs with $others';
+  }
+
   @override
   String get messageListGroupYouWithYourself => 'You with yourself';
 
@@ -310,6 +334,12 @@ class ZulipLocalizationsSk extends ZulipLocalizations {
   @override
   String get lightboxCopyLinkTooltip => 'Skopírovať odkaz';
 
+  @override
+  String get lightboxVideoCurrentPosition => 'Current position';
+
+  @override
+  String get lightboxVideoDuration => 'Video duration';
+
   @override
   String get loginPageTitle => 'Prihlásiť sa';
 
@@ -463,6 +493,9 @@ class ZulipLocalizationsSk extends ZulipLocalizations {
   @override
   String get recentDmConversationsPageTitle => 'Priama správa';
 
+  @override
+  String get recentDmConversationsSectionHeader => 'Direct messages';
+
   @override
   String get combinedFeedPageTitle => 'Zlúčený kanál';
 
@@ -492,9 +525,21 @@ class ZulipLocalizationsSk extends ZulipLocalizations {
     return '$senderFullName to you and $_temp0';
   }
 
+  @override
+  String get pinnedSubscriptionsLabel => 'Pinned';
+
+  @override
+  String get unpinnedSubscriptionsLabel => 'Unpinned';
+
+  @override
+  String get subscriptionListNoChannels => 'No channels found';
+
   @override
   String get notifSelfUser => 'Ty';
 
+  @override
+  String get reactedEmojiSelfUser => 'You';
+
   @override
   String onePersonTyping(String typist) {
     return '$typist píše…';
@@ -541,6 +586,11 @@ class ZulipLocalizationsSk extends ZulipLocalizations {
   @override
   String get messageIsMovedLabel => 'PRESUNUTÉ';
 
+  @override
+  String pollVoterNames(String voterNames) {
+    return '($voterNames)';
+  }
+
   @override
   String get pollWidgetQuestionMissing => 'Bez otázky.';
 
@@ -564,4 +614,10 @@ class ZulipLocalizationsSk extends ZulipLocalizations {
 
   @override
   String get emojiPickerSearchEmoji => 'Hľadať emotikon';
+
+  @override
+  String get noEarlierMessages => 'No earlier messages';
+
+  @override
+  String get scrollToBottomTooltip => 'Scroll to bottom';
 }
diff --git a/lib/model/compose.dart b/lib/model/compose.dart
index 13b9d59cf5..54c7f6ce00 100644
--- a/lib/model/compose.dart
+++ b/lib/model/compose.dart
@@ -1,6 +1,7 @@
 import 'dart:math';
 
 import '../api/model/model.dart';
+import '../generated/l10n/zulip_localizations.dart';
 import 'internal_link.dart';
 import 'narrow.dart';
 import 'store.dart';
@@ -182,7 +183,9 @@ String inlineLink(String visibleText, Uri? destination) {
 }
 
 /// What we show while fetching the target message's raw Markdown.
-String quoteAndReplyPlaceholder(PerAccountStore store, {
+String quoteAndReplyPlaceholder(
+  ZulipLocalizations zulipLocalizations,
+  PerAccountStore store, {
   required Message message,
 }) {
   final sender = store.users[message.senderId];
@@ -191,8 +194,8 @@ String quoteAndReplyPlaceholder(PerAccountStore store, {
     SendableNarrow.ofMessage(message, selfUserId: store.selfUserId),
     nearMessageId: message.id);
   // See note in [quoteAndReply] about asking `mention` to omit the |<id> part.
-  return '${userMention(sender!, silent: true)} ${inlineLink('said', url)}: ' // TODO(i18n) ?
-    '*(loading message ${message.id})*\n'; // TODO(i18n) ?
+  return '${userMention(sender!, silent: true)} ${inlineLink('said', url)}: ' // TODO(#1285)
+    '*${zulipLocalizations.composeBoxLoadingMessage(message.id)}*\n';
 }
 
 /// Quote-and-reply syntax.
@@ -215,6 +218,6 @@ String quoteAndReply(PerAccountStore store, {
     // Could ask `mention` to omit the |<id> part unless the mention is ambiguous…
     // but that would mean a linear scan through all users, and the extra noise
     // won't much matter with the already probably-long message link in there too.
-    return '${userMention(sender!, silent: true)} ${inlineLink('said', url)}:\n' // TODO(i18n) ?
+    return '${userMention(sender!, silent: true)} ${inlineLink('said', url)}:\n' // TODO(#1285)
       '${wrapWithBacktickFence(content: rawContent, infoString: 'quote')}';
 }
diff --git a/lib/notifications/display.dart b/lib/notifications/display.dart
index 8319ee65b1..b897530c21 100644
--- a/lib/notifications/display.dart
+++ b/lib/notifications/display.dart
@@ -204,7 +204,7 @@ class NotificationChannelManager {
 
     await _androidHost.createNotificationChannel(NotificationChannel(
       id: kChannelId,
-      name: 'Messages', // TODO(i18n)
+      name: 'Messages', // TODO(#1284)
       importance: NotificationImportance.high,
       lightsEnabled: true,
       soundUrl: defaultSoundUrl,
@@ -263,7 +263,7 @@ class NotificationDisplayManager {
       FcmMessageChannelRecipient(:var streamName?, :var topic) =>
         '#$streamName > ${topic.displayName}',
       FcmMessageChannelRecipient(:var topic) =>
-        '#(unknown channel) > ${topic.displayName}', // TODO get stream name from data
+        '#${zulipLocalizations.unknownChannelName} > ${topic.displayName}', // TODO get stream name from data
       FcmMessageDmRecipient(:var allRecipientIds) when allRecipientIds.length > 2 =>
         zulipLocalizations.notifGroupDmConversationLabel(
           data.senderFullName, allRecipientIds.length - 2), // TODO use others' names, from data
diff --git a/lib/widgets/action_sheet.dart b/lib/widgets/action_sheet.dart
index 6a90b61e64..3eff182bca 100644
--- a/lib/widgets/action_sheet.dart
+++ b/lib/widgets/action_sheet.dart
@@ -665,7 +665,9 @@ class QuoteAndReplyButton extends MessageActionSheetMenuItemButton {
     // This inserts a "[Quoting…]" placeholder into the content input,
     // giving the user a form of progress feedback.
     final tag = composeBoxController.content
-      .registerQuoteAndReplyStart(PerAccountStoreWidget.of(pageContext),
+      .registerQuoteAndReplyStart(
+        zulipLocalizations,
+        PerAccountStoreWidget.of(pageContext),
         message: message,
       );
 
diff --git a/lib/widgets/app.dart b/lib/widgets/app.dart
index 75fec7bc8b..9525dffdfe 100644
--- a/lib/widgets/app.dart
+++ b/lib/widgets/app.dart
@@ -323,6 +323,7 @@ class ChooseAccountPageOverflowButton extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
+    final zulipLocalizations = ZulipLocalizations.of(context);
     final materialLocalizations = MaterialLocalizations.of(context);
     return MenuAnchor(
       menuChildren: [
@@ -330,7 +331,7 @@ class ChooseAccountPageOverflowButton extends StatelessWidget {
           onPressed: () {
             Navigator.push(context, AboutZulipPage.buildRoute(context));
           },
-          child: const Text('About Zulip')), // TODO(i18n)
+          child: Text(zulipLocalizations.aboutPageTitle)),
       ],
       builder: (BuildContext context, MenuController controller, Widget? child) {
         return IconButton(
diff --git a/lib/widgets/compose_box.dart b/lib/widgets/compose_box.dart
index 3058425bf1..9ee87754b8 100644
--- a/lib/widgets/compose_box.dart
+++ b/lib/widgets/compose_box.dart
@@ -266,10 +266,15 @@ class ComposeContentController extends ComposeController<ContentValidationError>
   ///
   /// Returns an int "tag" that should be passed to registerQuoteAndReplyEnd on
   /// success or failure
-  int registerQuoteAndReplyStart(PerAccountStore store, {required Message message}) {
+  int registerQuoteAndReplyStart(
+    ZulipLocalizations zulipLocalizations,
+    PerAccountStore store, {
+      required Message message,
+    }) {
     final tag = _nextQuoteAndReplyTag;
     _nextQuoteAndReplyTag += 1;
-    final placeholder = quoteAndReplyPlaceholder(store, message: message);
+    final placeholder = quoteAndReplyPlaceholder(
+      zulipLocalizations, store, message: message);
     _quoteAndReplies[tag] = (messageId: message.id, placeholder: placeholder);
     notifyListeners(); // _quoteAndReplies change could affect validationErrors
     insertPadded(placeholder);
@@ -574,7 +579,7 @@ class _StreamContentInputState extends State<_StreamContentInput> {
     final store = PerAccountStoreWidget.of(context);
     final zulipLocalizations = ZulipLocalizations.of(context);
     final streamName = store.streams[widget.narrow.streamId]?.name
-      ?? zulipLocalizations.composeBoxUnknownChannelName;
+      ?? zulipLocalizations.unknownChannelName;
     return _ContentInput(
       narrow: widget.narrow,
       destination: TopicNarrow(widget.narrow.streamId, TopicName(_topicTextNormalized)),
@@ -636,7 +641,7 @@ class _FixedDestinationContentInput extends StatelessWidget {
       case TopicNarrow(:final streamId, :final topic):
         final store = PerAccountStoreWidget.of(context);
         final streamName = store.streams[streamId]?.name
-          ?? zulipLocalizations.composeBoxUnknownChannelName;
+          ?? zulipLocalizations.unknownChannelName;
         return zulipLocalizations.composeBoxChannelContentHint(
           streamName, topic.displayName);
 
diff --git a/lib/widgets/content.dart b/lib/widgets/content.dart
index f3b369e876..02c4f05ca3 100644
--- a/lib/widgets/content.dart
+++ b/lib/widgets/content.dart
@@ -1319,10 +1319,11 @@ class MessageTableCell extends StatelessWidget {
 
 void _launchUrl(BuildContext context, String urlString) async {
   DialogStatus showError(BuildContext context, String? message) {
+    final zulipLocalizations = ZulipLocalizations.of(context);
     return showErrorDialog(context: context,
-      title: 'Unable to open link',
+      title: zulipLocalizations.errorCouldNotOpenLinkTitle,
       message: [
-        'Link could not be opened: $urlString',
+        zulipLocalizations.errorCouldNotOpenLink(urlString),
         if (message != null) message,
       ].join("\n\n"));
   }
@@ -1570,6 +1571,7 @@ InlineSpan _errorUnimplemented(UnimplementedNode node, {required BuildContext co
   // because release mode isn't yet about general users but developer demos,
   // and we want to keep the demos honest.
   // TODO(#194) think through UX for general release
+  // TODO(#1285) translate this
   final htmlNode = node.htmlNode;
   if (htmlNode is dom.Element) {
     return TextSpan(children: [
diff --git a/lib/widgets/emoji_reaction.dart b/lib/widgets/emoji_reaction.dart
index 3d69e3d0d1..de3e2baa26 100644
--- a/lib/widgets/emoji_reaction.dart
+++ b/lib/widgets/emoji_reaction.dart
@@ -147,6 +147,7 @@ class ReactionChip extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     final store = PerAccountStoreWidget.of(context);
+    final zulipLocalizations = ZulipLocalizations.of(context);
 
     final reactionType = reactionWithVotes.reactionType;
     final emojiCode = reactionWithVotes.emojiCode;
@@ -160,8 +161,8 @@ class ReactionChip extends StatelessWidget {
       //   // 'Chris、Greg、Alya、Shu'
       ? userIds.map((id) {
           return id == store.selfUserId
-            ? 'You'
-            : store.users[id]?.fullName ?? '(unknown user)'; // TODO(i18n)
+            ? zulipLocalizations.reactedEmojiSelfUser
+            : store.users[id]?.fullName ?? zulipLocalizations.unknownUserName;
         }).join(', ')
       : userIds.length.toString();
 
diff --git a/lib/widgets/inbox.dart b/lib/widgets/inbox.dart
index 598b99beac..6dbe31ce04 100644
--- a/lib/widgets/inbox.dart
+++ b/lib/widgets/inbox.dart
@@ -1,6 +1,7 @@
 import 'package:flutter/material.dart';
 
 import '../api/model/model.dart';
+import '../generated/l10n/zulip_localizations.dart';
 import '../model/narrow.dart';
 import '../model/recent_dm_conversations.dart';
 import '../model/unreads.dart';
@@ -237,7 +238,7 @@ abstract class _HeaderItem extends StatelessWidget {
     required this.sectionContext,
   });
 
-  String get title;
+  String title(ZulipLocalizations zulipLocalizations);
   IconData get icon;
   Color collapsedIconColor(BuildContext context);
   Color uncollapsedIconColor(BuildContext context);
@@ -257,6 +258,7 @@ abstract class _HeaderItem extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
+    final zulipLocalizations = ZulipLocalizations.of(context);
     final designVariables = DesignVariables.of(context);
     return Material(
       color: collapsed
@@ -291,7 +293,7 @@ abstract class _HeaderItem extends StatelessWidget {
               ).merge(weightVariableTextStyle(context, wght: 600)),
               maxLines: 1,
               overflow: TextOverflow.ellipsis,
-              title))),
+              title(zulipLocalizations)))),
           const SizedBox(width: 12),
           if (hasMention) const _IconMarker(icon: ZulipIcons.at_sign),
           Padding(padding: const EdgeInsetsDirectional.only(end: 16),
@@ -312,7 +314,8 @@ class _AllDmsHeaderItem extends _HeaderItem {
     required super.sectionContext,
   });
 
-  @override String get title => 'Direct messages'; // TODO(i18n)
+  @override String title(ZulipLocalizations zulipLocalizations) =>
+    zulipLocalizations.recentDmConversationsSectionHeader;
   @override IconData get icon => ZulipIcons.user;
 
   // TODO(design) check if this is the right variable for these
@@ -381,16 +384,20 @@ class _DmItem extends StatelessWidget {
     final store = PerAccountStoreWidget.of(context);
     final selfUser = store.users[store.selfUserId]!;
 
+    final zulipLocalizations = ZulipLocalizations.of(context);
     final designVariables = DesignVariables.of(context);
 
     final title = switch (narrow.otherRecipientIds) { // TODO dedupe with [RecentDmConversationsItem]
       [] => selfUser.fullName,
-      [var otherUserId] => store.users[otherUserId]?.fullName ?? '(unknown user)',
+      [var otherUserId] =>
+        store.users[otherUserId]?.fullName ?? zulipLocalizations.unknownUserName,
 
       // TODO(i18n): List formatting, like you can do in JavaScript:
       //   new Intl.ListFormat('ja').format(['Chris', 'Greg', 'Alya', 'Shu'])
       //   // 'Chris、Greg、Alya、Shu'
-      _ => narrow.otherRecipientIds.map((id) => store.users[id]?.fullName ?? '(unknown user)').join(', '),
+      _ => narrow.otherRecipientIds.map(
+        (id) => store.users[id]?.fullName ?? zulipLocalizations.unknownUserName
+      ).join(', '),
     };
 
     return Material(
@@ -436,7 +443,8 @@ class _StreamHeaderItem extends _HeaderItem {
     required super.sectionContext,
   });
 
-  @override String get title => subscription.name;
+  @override String title(ZulipLocalizations zulipLocalizations) =>
+    subscription.name;
   @override IconData get icon => iconDataForStream(subscription);
   @override Color collapsedIconColor(context) =>
     colorSwatchFor(context, subscription).iconOnPlainBackground;
diff --git a/lib/widgets/lightbox.dart b/lib/widgets/lightbox.dart
index 4635e496f4..1406b5fdbd 100644
--- a/lib/widgets/lightbox.dart
+++ b/lib/widgets/lightbox.dart
@@ -385,13 +385,14 @@ class _VideoPositionSliderControlState extends State<_VideoPositionSliderControl
 
   @override
   Widget build(BuildContext context) {
+    final zulipLocalizations = ZulipLocalizations.of(context);
     final currentPosition = _isSliderDragging
       ? _sliderValue
       : widget.controller.value.position;
 
     return Row(children: [
       VideoDurationLabel(currentPosition,
-        semanticsLabel: "Current position"),
+        semanticsLabel: zulipLocalizations.lightboxVideoCurrentPosition),
       Expanded(
         child: Slider(
           value: currentPosition.inMilliseconds.toDouble(),
@@ -421,7 +422,7 @@ class _VideoPositionSliderControlState extends State<_VideoPositionSliderControl
         ),
       ),
       VideoDurationLabel(widget.controller.value.duration,
-        semanticsLabel: "Video duration"),
+        semanticsLabel: zulipLocalizations.lightboxVideoDuration),
     ]);
   }
 }
diff --git a/lib/widgets/message_list.dart b/lib/widgets/message_list.dart
index bd85c03c05..0d1a936dff 100644
--- a/lib/widgets/message_list.dart
+++ b/lib/widgets/message_list.dart
@@ -335,6 +335,7 @@ class MessageListAppBarTitle extends StatelessWidget {
   Widget _buildStreamRow(BuildContext context, {
     ZulipStream? stream,
   }) {
+    final zulipLocalizations = ZulipLocalizations.of(context);
     // A null [Icon.icon] makes a blank space.
     final icon = stream != null ? iconDataForStream(stream) : null;
     return Row(
@@ -346,7 +347,8 @@ class MessageListAppBarTitle extends StatelessWidget {
       children: [
         Icon(size: 16, icon),
         const SizedBox(width: 4),
-        Flexible(child: Text(stream?.name ?? '(unknown channel)')),
+        Flexible(child: Text(
+          stream?.name ?? zulipLocalizations.unknownChannelName)),
       ]);
   }
 
@@ -413,10 +415,13 @@ class MessageListAppBarTitle extends StatelessWidget {
       case DmNarrow(:var otherRecipientIds):
         final store = PerAccountStoreWidget.of(context);
         if (otherRecipientIds.isEmpty) {
-          return const Text("DMs with yourself");
+          return Text(zulipLocalizations.dmsWithYourselfPageTitle);
         } else {
-          final names = otherRecipientIds.map((id) => store.users[id]?.fullName ?? '(unknown user)');
-          return Text("DMs with ${names.join(", ")}"); // TODO show avatars
+          final names = otherRecipientIds.map(
+            (id) => store.users[id]?.fullName ?? zulipLocalizations.unknownUserName);
+          // TODO show avatars
+          return Text(
+            zulipLocalizations.dmsWithOthersPageTitle(names.join(', ')));
         }
     }
   }
@@ -568,6 +573,7 @@ class _MessageListState extends State<MessageList> with PerAccountStoreAwareStat
   Widget _buildListView(BuildContext context) {
     final length = model!.items.length;
     const centerSliverKey = ValueKey('center sliver');
+    final zulipLocalizations = ZulipLocalizations.of(context);
 
     Widget sliver = SliverStickyHeaderList(
       headerPlacement: HeaderPlacement.scrollingStart,
@@ -604,7 +610,7 @@ class _MessageListState extends State<MessageList> with PerAccountStoreAwareStat
           if (i == 2) return TypingStatusWidget(narrow: widget.narrow);
 
           final data = model!.items[length - 1 - (i - 3)];
-          return _buildItem(data, i);
+          return _buildItem(zulipLocalizations, data, i);
         }));
 
     if (!ComposeBox.hasComposeBox(widget.narrow)) {
@@ -640,13 +646,13 @@ class _MessageListState extends State<MessageList> with PerAccountStoreAwareStat
       ]);
   }
 
-  Widget _buildItem(MessageListItem data, int i) {
+  Widget _buildItem(ZulipLocalizations zulipLocalizations, MessageListItem data, int i) {
     switch (data) {
       case MessageListHistoryStartItem():
-        return const Center(
+        return Center(
           child: Padding(
-            padding: EdgeInsets.symmetric(vertical: 16.0),
-            child: Text("No earlier messages."))); // TODO use an icon
+            padding: const EdgeInsets.symmetric(vertical: 16.0),
+            child: Text(zulipLocalizations.noEarlierMessages))); // TODO use an icon
       case MessageListLoadingItem():
         return const Center(
           child: Padding(
@@ -690,6 +696,7 @@ class ScrollToBottomButton extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
+    final zulipLocalizations = ZulipLocalizations.of(context);
     return ValueListenableBuilder<bool>(
       valueListenable: visibleValue,
       builder: (BuildContext context, bool value, Widget? child) {
@@ -697,7 +704,7 @@ class ScrollToBottomButton extends StatelessWidget {
       },
       // TODO: fix hardcoded values for size and style here
       child: IconButton(
-        tooltip: "Scroll to bottom",
+        tooltip: zulipLocalizations.scrollToBottomTooltip,
         icon: const Icon(Icons.expand_circle_down_rounded),
         iconSize: 40,
         // Web has the same color in light and dark mode.
@@ -1030,6 +1037,7 @@ class StreamMessageRecipientHeader extends StatelessWidget {
     //   https://github.com/zulip/zulip-mobile/issues/5511
     final store = PerAccountStoreWidget.of(context);
     final designVariables = DesignVariables.of(context);
+    final zulipLocalizations = ZulipLocalizations.of(context);
 
     final topic = message.topic;
 
@@ -1054,7 +1062,7 @@ class StreamMessageRecipientHeader extends StatelessWidget {
       final stream = store.streams[message.streamId];
       final streamName = stream?.name
         ?? message.displayRecipient
-        ?? '(unknown channel)'; // TODO(log)
+        ?? zulipLocalizations.unknownChannelName; // TODO(log)
 
       streamWidget = GestureDetector(
         onTap: () => Navigator.push(context,
diff --git a/lib/widgets/poll.dart b/lib/widgets/poll.dart
index 07123fe196..dc340d08b8 100644
--- a/lib/widgets/poll.dart
+++ b/lib/widgets/poll.dart
@@ -126,8 +126,8 @@ class _PollWidgetState extends State<PollWidget> {
                 children: [
                   Text(option.text, style: textStyleBold.copyWith(fontSize: 16)),
                   if (option.voters.isNotEmpty)
-                    // TODO(i18n): Localize parenthesis characters.
-                    Text('($voterNames)', style: textStyleVoterNames),
+                    Text(zulipLocalizations.pollVoterNames(voterNames),
+                      style: textStyleVoterNames),
                 ]))),
         ]);
     }
diff --git a/lib/widgets/profile.dart b/lib/widgets/profile.dart
index 57dd76a0ab..f38daf792d 100644
--- a/lib/widgets/profile.dart
+++ b/lib/widgets/profile.dart
@@ -121,17 +121,18 @@ class _ProfileErrorPage extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
+    final zulipLocalizations = ZulipLocalizations.of(context);
     return Scaffold(
-      appBar: ZulipAppBar(title: const Text('Error')),
-      body: const SingleChildScrollView(
+      appBar: ZulipAppBar(title: Text(zulipLocalizations.errorDialogTitle)),
+      body: SingleChildScrollView(
         child: Padding(
-          padding: EdgeInsets.symmetric(horizontal: 16, vertical: 32),
+          padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 32),
           child: Row(
             mainAxisAlignment: MainAxisAlignment.center,
             children: [
-              Icon(Icons.error),
-              SizedBox(width: 4),
-              Text('Could not show user profile.'),
+              const Icon(Icons.error),
+              const SizedBox(width: 4),
+              Text(zulipLocalizations.errorCouldNotShowUserProfile),
             ]))));
   }
 }
@@ -290,8 +291,9 @@ class _UserWidget extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     final store = PerAccountStoreWidget.of(context);
+    final zulipLocalizations = ZulipLocalizations.of(context);
     final user = store.users[userId];
-    final fullName = user?.fullName ?? '(unknown user)';
+    final fullName = user?.fullName ?? zulipLocalizations.unknownUserName;
     return InkWell(
       onTap: () => Navigator.push(context,
         ProfilePage.buildRoute(context: context,
diff --git a/lib/widgets/recent_dm_conversations.dart b/lib/widgets/recent_dm_conversations.dart
index c9d3131591..ddc32861a3 100644
--- a/lib/widgets/recent_dm_conversations.dart
+++ b/lib/widgets/recent_dm_conversations.dart
@@ -1,5 +1,6 @@
 import 'package:flutter/material.dart';
 
+import '../generated/l10n/zulip_localizations.dart';
 import '../model/narrow.dart';
 import '../model/recent_dm_conversations.dart';
 import '../model/unreads.dart';
@@ -81,6 +82,7 @@ class RecentDmConversationsItem extends StatelessWidget {
     final store = PerAccountStoreWidget.of(context);
     final selfUser = store.users[store.selfUserId]!;
 
+    final zulipLocalizations = ZulipLocalizations.of(context);
     final designVariables = DesignVariables.of(context);
 
     final String title;
@@ -94,13 +96,15 @@ class RecentDmConversationsItem extends StatelessWidget {
         //   (should we offer a "spam folder" style summary screen of recent
         //   1:1 DM conversations from muted users?)
         final otherUser = store.users[otherUserId];
-        title = otherUser?.fullName ?? '(unknown user)';
+        title = otherUser?.fullName ?? zulipLocalizations.unknownUserName;
         avatar = AvatarImage(userId: otherUserId, size: _avatarSize);
       default:
         // TODO(i18n): List formatting, like you can do in JavaScript:
         //   new Intl.ListFormat('ja').format(['Chris', 'Greg', 'Alya'])
         //   // 'Chris、Greg、Alya'
-        title = narrow.otherRecipientIds.map((id) => store.users[id]?.fullName ?? '(unknown user)').join(', ');
+        title = narrow.otherRecipientIds.map(
+          (id) => store.users[id]?.fullName ?? zulipLocalizations.unknownUserName
+        ).join(', ');
         avatar = ColoredBox(color: designVariables.groupDmConversationIconBg,
           child: Center(
             child: Icon(color: designVariables.groupDmConversationIcon,
diff --git a/lib/widgets/subscription_list.dart b/lib/widgets/subscription_list.dart
index 07f9b84c4a..a51e722b51 100644
--- a/lib/widgets/subscription_list.dart
+++ b/lib/widgets/subscription_list.dart
@@ -1,6 +1,7 @@
 import 'package:flutter/material.dart';
 
 import '../api/model/model.dart';
+import '../generated/l10n/zulip_localizations.dart';
 import '../model/narrow.dart';
 import '../model/unreads.dart';
 import 'icons.dart';
@@ -77,10 +78,8 @@ class _SubscriptionListPageBodyState extends State<SubscriptionListPageBody> wit
 
     // TODO: Implement collapsible topics
 
-    // TODO(i18n): localize strings on page
-    //   Strings here left unlocalized as they likely will not
-    //   exist in the settled design.
     final store = PerAccountStoreWidget.of(context);
+    final zulipLocalizations = ZulipLocalizations.of(context);
 
     final List<Subscription> pinned = [];
     final List<Subscription> unpinned = [];
@@ -102,11 +101,11 @@ class _SubscriptionListPageBodyState extends State<SubscriptionListPageBody> wit
           if (pinned.isEmpty && unpinned.isEmpty)
             const _NoSubscriptionsItem(),
           if (pinned.isNotEmpty) ...[
-            const _SubscriptionListHeader(label: "Pinned"),
+            _SubscriptionListHeader(label: zulipLocalizations.pinnedSubscriptionsLabel),
             _SubscriptionList(unreadsModel: unreadsModel, subscriptions: pinned),
           ],
           if (unpinned.isNotEmpty) ...[
-            const _SubscriptionListHeader(label: "Unpinned"),
+            _SubscriptionListHeader(label: zulipLocalizations.unpinnedSubscriptionsLabel),
             _SubscriptionList(unreadsModel: unreadsModel, subscriptions: unpinned),
           ],
 
@@ -124,11 +123,12 @@ class _NoSubscriptionsItem extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     final designVariables = DesignVariables.of(context);
+    final zulipLocalizations = ZulipLocalizations.of(context);
 
     return SliverToBoxAdapter(
       child: Padding(
         padding: const EdgeInsets.all(10),
-        child: Text("No channels found",
+        child: Text(zulipLocalizations.subscriptionListNoChannels,
           textAlign: TextAlign.center,
           style: TextStyle(
             color: designVariables.subscriptionListHeaderText,
diff --git a/test/model/compose_test.dart b/test/model/compose_test.dart
index ceda0d4cd6..73fa9452d7 100644
--- a/test/model/compose_test.dart
+++ b/test/model/compose_test.dart
@@ -1,6 +1,7 @@
 import 'package:checks/checks.dart';
 import 'package:test/scaffolding.dart';
 import 'package:zulip/model/compose.dart';
+import 'package:zulip/model/localizations.dart';
 import 'package:zulip/model/store.dart';
 
 import '../example_data.dart' as eg;
@@ -288,7 +289,8 @@ hello
     await store.addStream(stream);
     await store.addUser(sender);
 
-    check(quoteAndReplyPlaceholder(store, message: message)).equals('''
+    check(quoteAndReplyPlaceholder(
+      GlobalLocalizations.zulipLocalizations, store, message: message)).equals('''
 @_**Full Name|123** [said](${eg.selfAccount.realmUrl}#narrow/stream/1-test-here/topic/some.20topic/near/${message.id}): *(loading message ${message.id})*
 ''');
 
diff --git a/test/widgets/action_sheet_test.dart b/test/widgets/action_sheet_test.dart
index e6b48384b8..2bb07b4946 100644
--- a/test/widgets/action_sheet_test.dart
+++ b/test/widgets/action_sheet_test.dart
@@ -641,7 +641,8 @@ void main() {
       }) {
         check(contentController).value.equals((ComposeContentController()
           ..value = valueBefore
-          ..insertPadded(quoteAndReplyPlaceholder(store, message: message))
+          ..insertPadded(quoteAndReplyPlaceholder(
+              GlobalLocalizations.zulipLocalizations, store, message: message))
         ).value);
         check(contentController).validationErrors.contains(ContentValidationError.quoteAndReplyInProgress);
       }