snapshot of https://github.com/zulip/zulip.git @ 48c69911c7dd4e03b20552eb3bd77ad8151c1357 (2026-09-15)

zerver/lib/zulip_update_announcements.py

@@ -0,0 +1,919 @@
+import logging
+from dataclasses import dataclass
+from datetime import timedelta
+
+from django.conf import settings
+from django.db import transaction
+from django.db.models import Q, QuerySet
+from django.utils.timezone import now as timezone_now
+from django.utils.translation import gettext as _
+from django.utils.translation import override as override_language
+
+from zerver.actions.message_send import (
+    do_send_messages,
+    internal_prep_group_direct_message,
+    internal_prep_stream_message,
+)
+from zerver.lib.exceptions import JsonableError
+from zerver.lib.message import SendMessageRequest, remove_single_newlines
+from zerver.lib.topic import messages_for_topic
+from zerver.models.realm_audit_logs import AuditLogEventType, RealmAuditLog
+from zerver.models.realms import Realm
+from zerver.models.streams import StreamTopicsPolicyEnum
+from zerver.models.users import UserProfile, get_system_bot
+
+
+@dataclass
+class ZulipUpdateAnnouncement:
+    level: int
+    message: str
+
+
+# We don't translate the announcement message because they are quite unlikely to be
+# translated during the time between when we draft them and when they are published.
+zulip_update_announcements: list[ZulipUpdateAnnouncement] = [
+    ZulipUpdateAnnouncement(
+        level=1,
+        message="""
+Zulip is introducing **Zulip updates**! To help you learn about new features and
+configuration options, this topic will receive messages about important changes in Zulip.
+
+You can read these update messages whenever it's convenient, or [mute]({mute_topic_help_url})
+this topic if you are not interested. If your organization does not want to receive these
+announcements, they can be disabled. [Learn more]({zulip_update_announcements_help_url}).
+""".format(
+            zulip_update_announcements_help_url="/help/configure-automated-notices#zulip-update-announcements",
+            mute_topic_help_url="/help/mute-a-topic",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=2,
+        message="""
+**Web and desktop updates**
+
+- When you paste content into the compose box, Zulip will now do its best to preserve
+the formatting, including links, bulleted lists, bold, italics, and more.
+Pasting as plain text remains an alternative option. [Learn
+more]({keyboard_shortcuts_basics_help_url}).
+- To [quote and reply]({quote_message_help_url}) to part of a message, you can
+now select the part that you want to quote.
+- You can now hide the user list in the right sidebar to reduce distraction.
+[Learn more]({user_list_help_url}).
+""".format(
+            keyboard_shortcuts_basics_help_url="/help/keyboard-shortcuts#the-basics",
+            user_list_help_url="/help/user-list",
+            quote_message_help_url="/help/quote-and-reply",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=3,
+        message="""
+- The **All messages** view has been renamed to **Combined feed**.
+[Learn more]({combined_feed_help_url}).
+
+**Web and desktop updates**
+- When you start composing, the most recently edited draft for the conversation
+you are composing to now automatically appears in the compose box. You can
+always save a draft and start a new message using the **send options** menu next
+to the **Send** button. [Learn more]({save_draft_help_url}).
+- If you'd prefer not to see notifications when others type, you can now disable
+them. [Learn more]({typing_notifications_help_url}).
+""".format(
+            typing_notifications_help_url="/help/typing-notifications",
+            combined_feed_help_url="/help/combined-feed",
+            save_draft_help_url="/help/view-and-edit-your-message-drafts#save-a-draft-and-start-a-new-message",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=4,
+        message="""
+- To simplify Zulip for new users, **Streams** have been renamed to **Channels**.
+The functionality remains exactly the same, and bots do not need
+to be updated. [Learn more]({introduction_to_channels_help_url}).
+
+- Topics and messages now load much faster when you open the web or desktop app.
+""".format(
+            introduction_to_channels_help_url="/help/introduction-to-channels",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=5,
+        message="""
+**Web and desktop updates**
+- Use the new **Reactions** view to see how others have reacted to your
+messages. [Learn more]({view_your_messages_with_reactions_help_url}).
+- For a more focused reading experience, you can now hide the
+[left]({left_sidebar_help_url}) and [right]({user_list_help_url})
+sidebars any time using the buttons in the top navigation bar. When the left
+sidebar is hidden, use [keyboard
+navigation]({keyboard_shortcuts_navigation_help_url}) to jump to the next unread
+topic or go back to your [home view]({configure_home_view_help_url}).
+- You can now search for messages in topics you
+  [follow]({follow_a_topic_help_url}) using the `is:followed` filter. [Learn
+  more]({search_by_message_status_help_url}).
+""".format(
+            view_your_messages_with_reactions_help_url="/help/emoji-reactions#view-your-messages-with-reactions",
+            left_sidebar_help_url="/help/left-sidebar",
+            user_list_help_url="/help/user-list",
+            keyboard_shortcuts_navigation_help_url="/help/keyboard-shortcuts#navigation",
+            configure_home_view_help_url="/help/configure-home-view",
+            follow_a_topic_help_url="/help/follow-a-topic",
+            search_by_message_status_help_url="/help/search-for-messages#search-by-message-status",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=6,
+        message="""
+**Web and desktop updates**
+- You can now configure whether channel links in the left sidebar go to the most
+recent topic (default option), or to the channel feed. With the default
+configuration, you can access the feed from the channel menu.
+[Learn more]({channel_feed_help_url}).
+- You can also [configure]({automatically_go_to_conversation_help_url}) whether Zulip
+automatically takes you to the conversation to which you sent a message, if you
+aren't already viewing it (on by default).
+- You can now [filter]({find_a_dm_conversation_help_url}) direct message
+conversations in the left sidebar to conversations that include a specific
+person.
+""".format(
+            channel_feed_help_url="/help/channel-feed",
+            automatically_go_to_conversation_help_url="/help/mastering-the-compose-box#automatically-go-to-conversation-where-you-sent-a-message",
+            find_a_dm_conversation_help_url="/help/direct-messages#find-a-direct-message-conversation",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=7,
+        message="""
+**Web and desktop updates**
+- To make reading more comfortable, Zulip has been redesigned with a larger font
+size and line spacing. If you prefer to see more content at once, [enable
+compact mode]({settings_preferences_url}) to go back to the previous design.
+- The main search has been redesigned with pills for [search
+filters]({search_help_url}), making it easier to use.
+- Pasted [channel and topic URLs]({link_help_url}) are now automatically
+converted into nicely formatted links.
+""".format(
+            settings_preferences_url="/#settings/preferences",
+            search_help_url="/help/search-for-messages",
+            link_help_url="/help/link-to-a-message-or-conversation",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=8,
+        message=(
+            """
+- New image uploads now load much faster in all Zulip apps.
+- In the desktop and web apps, you can now [configure]({image_previews_help_url})
+previews of animated images to **always show** the animation, show it **when you
+hover** over the image with your mouse (default), or **not show** it at all. You can
+always see the animated image by opening it in the [image
+viewer]({view_images_help_url})."""
+            + (
+                """
+
+We make many improvements to Zulip beyond what we can share here. Learn about
+additional feature highlights, and other Zulip project updates since December
+2023, in the [blog post]({blog_post_9_0_url}) announcing today's release of
+Zulip Server 9.0.
+"""
+                if settings.CORPORATE_ENABLED
+                else """
+
+We make many improvements to Zulip beyond what we can share here. Check out our
+[release announcement blog post]({blog_post_9_0_url}) to learn about additional
+feature highlights in Zulip Server 9.0, and other Zulip project updates.
+"""
+            )
+        ).format(
+            image_previews_help_url="/help/allow-image-link-previews",
+            view_images_help_url="/help/view-images-and-videos",
+            blog_post_9_0_url="https://blog.zulip.com/zulip-server-9-0",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=9,
+        message=(
+            (
+                """
+- You can now [upload large files]({file_upload_limits_help_url}) up to
+  1 GB in organizations on Zulip Cloud
+  Standard or Zulip Cloud Plus [plans]({cloud_plans_url}).
+"""
+                if settings.CORPORATE_ENABLED
+                else """
+- You can now [upload large files]({file_upload_limits_help_url}), up to
+  the limit configured by your server's administrator (currently {max_file_upload_size} MB).
+"""
+            )
+            + """
+
+**Web and desktop updates**
+- You can now start a new conversation from the left sidebar. Click the `+`
+button next to the name of a channel to [start a new
+topic]({how_to_start_a_new_topic_help_url}) in that channel, or the `+` next to
+DIRECT MESSAGES to [start a DM]({starting_a_new_direct_message_help_url}).
+- The [user list]({user_list_help_url}) now shows recent participants in the
+  conversation you're viewing.
+"""
+        ).format(
+            how_to_start_a_new_topic_help_url="/help/introduction-to-topics#how-to-start-a-new-topic",
+            starting_a_new_direct_message_help_url="/help/starting-a-new-direct-message",
+            user_list_help_url="/help/user-list",
+            cloud_plans_url="/plans/",
+            file_upload_limits_help_url="/help/share-and-upload-files#file-upload-limits",
+            max_file_upload_size=settings.MAX_FILE_UPLOAD_SIZE,
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=10,
+        message=(
+            """
+- Most permissions in Zulip can now be granted to any combination of
+  [roles]({roles_and_permissions_help_url}), [groups]({user_groups_help_url}),
+  and individual [users]({users_help_url}). Previously, permissions were
+  configurable only by user role."""
+            + (
+                """
+- Creating new user groups now requires a Zulip Cloud Standard or Zulip Cloud
+  Plus [plan]({cloud_plans_url}).
+"""
+                if settings.CORPORATE_ENABLED
+                else ""
+            )
+            + """
+
+**Web and desktop updates**
+- To provide more information, long topic names are now shown on two lines in
+  the left sidebar.
+- Pasted [message links]({message_links_help_url}) are now automatically
+  converted into nicely formatted links.
+"""
+        ).format(
+            roles_and_permissions_help_url="/help/roles-and-permissions",
+            user_groups_help_url="/help/user-groups",
+            users_help_url="/help/manage-a-user",
+            cloud_plans_url="/plans/",
+            message_links_help_url="/help/link-to-a-message-or-conversation#get-a-link-to-a-specific-message",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=11,
+        message="""
+- Zulip’s next-gen mobile app is now in public beta. If offers a sleek new
+  design and a faster, smoother experience. [Check out the announcement
+  post]({flutter_beta_blog_post}) for details and instructions on how to try the
+  beta!
+
+**Web and desktop updates**
+- There's a [new option]({user_list_style_help_url}) to show avatars in the
+  user list.
+- You can now conveniently [forward]({quote_or_forward_help_url}) a message to
+  another conversation from the message menu.
+""".format(
+            flutter_beta_blog_post="https://blog.zulip.com/2024/12/12/new-flutter-mobile-app-beta/",
+            user_list_style_help_url="/help/user-list#configure-user-list-style",
+            quote_or_forward_help_url="/help/quote-or-forward-a-message",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=12,
+        message="""
+- When you [link to a topic]({link_from_anywhere_help_url}) in Zulip, that link
+  will now continue to work even when the topic is
+  [renamed]({rename_a_topic_help_url}), [moved to another
+  channel]({move_content_to_another_channel_help_url}), or
+  [resolved]({resolve_a_topic_help_url}).
+
+**Web and desktop updates**
+- You can now [save snippets]({saved_snippets_help_url}) of message content, and
+quickly insert them into the message you're composing.
+- [Drafts]({drafts_help_url}) are no longer removed after 30 days.
+""".format(
+            link_from_anywhere_help_url="/help/link-to-a-message-or-conversation#link-to-zulip-from-anywhere",
+            rename_a_topic_help_url="/help/rename-a-topic",
+            move_content_to_another_channel_help_url="/help/move-content-to-another-channel",
+            resolve_a_topic_help_url="/help/resolve-a-topic",
+            saved_snippets_help_url="/help/saved-snippets",
+            drafts_help_url="/help/view-and-edit-your-message-drafts",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=13,
+        message="""
+- Zulip channels have a new space for **chatting without a topic** (e.g., social
+  chatter or one-off requests). Channel messages sent without a topic (if
+  [allowed]({require_topics_url}) in your organization) now go to a special
+  *[“general chat”]({general_chat_url})* topic. Its name appears in italics, and
+  will be translated into [your language]({change_your_language_url}).
+- New channel permission settings let administrators **delegate channel
+  management** responsibilities. There are settings for [who can
+  administer]({who_can_administer_url}) each channel, and who can
+  [subscribe]({who_can_subscribe_url}) and
+  [unsubscribe]({who_can_unsubscribe_url}) other users. You can also
+  [give]({configure_who_can_subscribe_url}) users and
+  [groups]({user_groups_url}) permission to read and subscribe to a
+  [private channel]({private_channels_url}), just like everyone other
+  than guests can do with public channels.
+
+**Web and desktop updates**
+- When you copy a Zulip link and paste it anywhere that accepts HTML formatting
+  (e.g., your email, GitHub, docs, etc.), the link will be formatted as it would
+  be in Zulip (e.g., [#channel > topic]({link_to_a_message_or_conversation_url})).
+- To [link]({link_to_a_message_or_conversation_url}) to a topic in the channel
+  you're composing to, you can now just type `#>` followed by a few letters from
+  the topic name, and pick the desired topic from the autocomplete.
+- There's a new compose box button for creating a [collaborative to-do
+  list]({to_do_list_url}).
+- You’ll now see a [typing notification]({typing_notifications_url}) when
+  someone is editing a message, not just for composing new messages.
+""".format(
+            require_topics_url="/help/require-topics",
+            general_chat_url="/help/general-chat-topic",
+            typing_notifications_url="/help/typing-notifications",
+            to_do_list_url="/help/collaborative-to-do-lists",
+            link_to_a_message_or_conversation_url="/help/link-to-a-message-or-conversation",
+            change_your_language_url="/help/change-your-language",
+            configure_who_can_subscribe_url="/help/configure-who-can-subscribe",
+            who_can_administer_url="/help/configure-who-can-administer-a-channel",
+            who_can_subscribe_url="/help/configure-who-can-invite-to-channels",
+            who_can_unsubscribe_url="/help/configure-who-can-unsubscribe-others",
+            user_groups_url="/help/user-groups",
+            private_channels_url="/help/channel-permissions#private-channels",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=14,
+        message="""
+**Web and desktop updates**
+- You can now choose from a wide range of [font size]({font_size_url})
+and [line spacing]({line_spacing_url}) options, to make the Zulip interface
+feel most comfortable for you.
+""".format(
+            font_size_url="/help/font-size",
+            line_spacing_url="/help/line-spacing",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=15,
+        message=(
+            """
+We make many improvements to Zulip beyond what we can share here. Learn about
+additional feature highlights, and other Zulip project updates since July
+2024, in the [blog post]({blog_post_10_0_url}) announcing today's release of
+Zulip Server 10.0.
+"""
+            if settings.CORPORATE_ENABLED
+            else """
+We make many improvements to Zulip beyond what we can share here. Check out our
+[release announcement blog post]({blog_post_10_0_url}) to learn about additional
+feature highlights in Zulip Server 10.0, and other Zulip project updates.
+"""
+        ).format(
+            blog_post_10_0_url="https://blog.zulip.com/zulip-server-10-0",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=16,
+        message="""
+- You can now [configure]({resolved_topic_notice_url}) whether notices sent when
+  topics are resolved are automatically marked as read for you.
+- You can now restore [deactivated groups]({deactivate_a_group_url}) and
+  [archived channels]({archive_a_channel_url}) if you need to use them again.
+""".format(
+            resolved_topic_notice_url="/help/marking-messages-as-read#configure-whether-resolved-topic-notices-are-marked-as-read",
+            archive_a_channel_url="/help/archive-a-channel",
+            deactivate_a_group_url="/help/deactivate-a-user-group",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=17,
+        message="""
+Starting this week, you’ll get Zulip’s next-generation mobile app the next time
+your Zulip app is upgraded. The new app offers a sleek new design and a faster,
+smoother experience. Check out [the announcement post]({flutter_release_blog_post})
+for details and how to share your feedback.
+""".format(
+            flutter_release_blog_post="https://blog.zulip.com/2025/06/17/flutter-mobile-app-launched/",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=18,
+        message="""
+- You can now [schedule yourself a direct message
+  reminder]({schedule_a_reminder_url}) about a message you want to come back to.
+- Permissions to [move]({restrict_moving_messages_url}) and
+  [resolve]({restrict_resolving_topics_url}) topics can now be configured
+  separately for each channel.
+
+**Mobile updates**
+
+We've been hard at work adding the most highly
+[requested]({what_about_feature_x_url}) features to the next-generation mobile
+app released in June.
+- You can now [search for messages]({search_for_messages_url}) in the mobile
+  app.
+- You can now see other users' [availability]({availability_url}) and
+  [status]({view_a_status_url}), and toggle [invisible
+  mode]({invisible_mode_url}).
+- You can check [who reacted]({view_who_reacted_url}) to a message, and [when
+  each message was sent]({view_exact_time_url}).
+
+**Web and desktop updates**
+- There are two new options for [where you
+  navigate]({left_sidebar_channel_links_url}) by clicking on a channel name in
+  the left sidebar: a [list of topics]({list_of_topics_url}) in the channel, or
+  the top unread topic.
+""".format(
+            schedule_a_reminder_url="/help/schedule-a-reminder",
+            restrict_moving_messages_url="/help/restrict-moving-messages",
+            restrict_resolving_topics_url="/help/restrict-resolving-topics",
+            what_about_feature_x_url="https://blog.zulip.com/2025/06/17/flutter-mobile-app-launched/#what-about-insert-feature-here",
+            left_sidebar_channel_links_url="/help/left-sidebar#configure-where-channel-links-in-the-left-sidebar-go",
+            list_of_topics_url="/help/list-of-topics",
+            search_for_messages_url="/help/search-for-messages",
+            availability_url="/help/status-and-availability#availability",
+            view_a_status_url="/help/status-and-availability#view-a-status",
+            invisible_mode_url="/help/status-and-availability#toggle-invisible-mode",
+            view_who_reacted_url="/help/emoji-reactions#view-who-reacted-to-a-message",
+            view_exact_time_url="/help/view-the-exact-time-a-message-was-sent",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=19,
+        message="""
+- Zulip's topics help you keep conversations organized, but you may not need
+  topics in some channels (e.g., a social channel, or one with a narrow
+  purpose). For these situations, you can now [configure “general chat”
+  channels]({general_chat_channels_url}) without topics.
+
+**Web and desktop updates**
+- When viewing all topics in a channel in the left sidebar, you can now [filter
+  topics]({filter_by_whether_resolved_url}) by whether they are resolved.
+- Your [home view]({home_view_url}) menu now has an option to [mark as
+  read]({marking_messages_as_read_url}) all messages in muted topics or topics
+  you don't follow. Zulip is snappier when you don't have thousands of unread
+  messages.
+""".format(
+            general_chat_channels_url="/help/general-chat-channels",
+            home_view_url="/help/configure-home-view",
+            marking_messages_as_read_url="/help/marking-messages-as-read",
+            filter_by_whether_resolved_url="/help/resolve-a-topic#filter-by-whether-topics-are-resolved",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=20,
+        message="""
+- Administrators can now organize channels into [folders]({channel_folders_url})
+  (e.g., a dedicated folder for a team's channels), and
+  [sort]({reorder_channel_folders_url}) folders as needed. Channels are grouped
+  by folder in the [Inbox]({inbox_url}) view, and each person can
+  [decide]({configure_left_sidebar_folders_url}) whether to group channels by
+  folder in the left sidebar.
+- Administrators can now [configure]({configure_a_custom_welcome_message_url}) a
+  custom welcome message for new users. For example, you can describe the
+  purpose of important channels, and link to your guidelines for using Zulip.
+
+**Web and desktop updates**
+- A new filter in the upper left lets you filter everything in your [left
+  sidebar]({left_sidebar_url}).
+
+**Mobile updates**
+- You can now [set your status]({set_a_status_url}).
+- Android users can now [share]({share_and_upload_files_url}) files and text
+  from other applications into Zulip.
+- You can now [check]({read_receipts_url}) who has read a message.
+- You will now see autocomplete suggestions for mentioning
+  [user groups]({user_groups_url}), as well as users.
+
+""".format(
+            channel_folders_url="/help/channel-folders",
+            reorder_channel_folders_url="/help/manage-channel-folders#reorder-channel-folders",
+            inbox_url="/help/inbox",
+            configure_left_sidebar_folders_url="/help/channel-folders#configure-whether-channels-are-grouped-by-folder-in-the-left-sidebar",
+            left_sidebar_url="/help/left-sidebar",
+            configure_a_custom_welcome_message_url="/help/configure-a-custom-welcome-message",
+            set_a_status_url="/help/status-and-availability#set-a-status",
+            share_and_upload_files_url="/help/share-and-upload-files",
+            read_receipts_url="/help/read-receipts",
+            user_groups_url="/help/user-groups",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=21,
+        message=(
+            """
+We make many improvements to Zulip beyond what we can share here. Learn about
+additional feature highlights, and other Zulip project updates since March,
+in the [blog post]({blog_post_11_0_url}) announcing today's release of
+Zulip Server 11.0.
+"""
+            if settings.CORPORATE_ENABLED
+            else """
+We make many improvements to Zulip beyond what we can share here. Check out our
+[release announcement blog post]({blog_post_11_0_url}) to learn about additional
+feature highlights in Zulip Server 11.0, and other Zulip project updates.
+"""
+        ).format(
+            blog_post_11_0_url="https://blog.zulip.com/zulip-server-11-0",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=22,
+        message="""
+The [help center]({help_url}) has a new, modernized design, complete with
+light and dark theme. A search bar makes it easier to find the information you
+need, whether it's how to get started, specific features, best practices, or
+administrative capabilities.
+
+**Mobile updates**
+- You can now [browse]({browse_and_subscribe_url}) channels you're not
+  subscribed to, and subscribe.
+- You can now [delete messages]({delete_message_completely}), if you have
+  permission to do so.
+- Android users can now paste an image into a message, or insert a sticker from
+  the keyboard.
+""".format(
+            browse_and_subscribe_url="/help/introduction-to-channels#browse-and-subscribe-to-channels",
+            delete_message_completely="/help/delete-a-message#delete-a-message-completely",
+            help_url="/help/",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=23,
+        message="""
+**Web and desktop updates**
+- You can now [report]({report_a_message_url}) problematic messages if
+moderation requests are [enabled]({enable_moderation_requests_url}).
+- You can now [expand or collapse]({expand_or_collapse_sections_url}) all sections in the left sidebar, and
+[configure]({configure_inbox_folders_url}) whether channels are grouped by
+folder in the inbox view.
+""".format(
+            report_a_message_url="/help/report-a-message",
+            enable_moderation_requests_url="/help/enable-moderation-requests",
+            expand_or_collapse_sections_url="/help/left-sidebar#expand-or-collapse-sections",
+            configure_inbox_folders_url="/help/channel-folders#configure-whether-channels-are-grouped-by-folder-in-the-inbox-view",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=24,
+        message="""
+**Web and desktop updates**
+- The [recent conversations view]({recent_conversations_url}) has been
+redesigned, with a new option to [filter by folder]({filter_by_folder_url}).
+- [Search]({search_url}) typeahead now suggests topics across all your
+subscribed channels — no need to pick a channel first.
+
+**New organization settings**
+- [Size of image and video previews]({image_video_thumbnail_size_url}) in the message feed.
+- Configure [linkifiers]({linkifiers_url}) to also work in reverse: when you paste a URL that
+matches the linkifier, Zulip will automatically convert it to linkified text.
+- You can now create [custom profile fields]({custom_profile_fields_url}) for many types of external
+accounts, and allow them to be used for @-mention suggestions.
+- A new option for [default profile pictures for new
+users]({configure_default_profile_pictures_url}) looks great in both light and
+dark theme.
+
+Administrators can now [reset]({reset_settings_for_users_url}) any non-privacy
+user preference or notification setting to the [organization
+default]({configure_default_new_user_settings_url}), for everyone or just for
+users who haven't personally configured it.
+""".format(
+            recent_conversations_url="/help/recent-conversations",
+            filter_by_folder_url="/help/recent-conversations#filter-by-folder",
+            search_url="/help/search-for-messages",
+            image_video_thumbnail_size_url="/help/image-video-and-website-previews#configure-image-and-video-thumbnail-size",
+            linkifiers_url="/help/add-a-custom-linkifier",
+            custom_profile_fields_url="/help/custom-profile-fields",
+            configure_default_profile_pictures_url="/help/configure-default-profile-pictures",
+            reset_settings_for_users_url="/help/reset-settings-for-users",
+            configure_default_new_user_settings_url="/help/configure-default-new-user-settings",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=25,
+        message="""
+**Web and desktop updates**
+- You can now instantly [scroll to any date]({scroll_to_date_url}) in the
+message feed, whether you're viewing a conversation, a channel feed, search
+results, or anything else.
+- You can now [quote or forward]({quote_or_forward_url}) selected text from
+several messages at once using the `>` and `<` keyboard shortcuts.
+""".format(
+            scroll_to_date_url="/help/scroll-to-date",
+            quote_or_forward_url="/help/quote-or-forward-a-message",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=26,
+        message="""
+Zulip now [encrypts]({mobile_notifications_e2ee_url}) your push notifications
+end to end from the Zulip server to your mobile device when you use version
+30.0.272+ of the mobile app.
+
+**Web and desktop updates**
+- You can now [search]({search_your_important_messages_url}) for messages that
+mention any user with the `mentions:` filter.
+
+""".format(
+            mobile_notifications_e2ee_url="/help/mobile-notifications#end-to-end-encryption-e2ee-for-mobile-push-notifications",
+            search_your_important_messages_url="/help/search-for-messages#search-your-important-messages",
+        ),
+    ),
+    ZulipUpdateAnnouncement(
+        level=27,
+        message=(
+            """
+We make many improvements to Zulip beyond what we can share here. Learn about
+additional feature highlights, and other Zulip project updates since last
+August, in the [blog post]({blog_post_12_0_url}) announcing today's release of
+Zulip Server 12.0.
+"""
+            if settings.CORPORATE_ENABLED
+            else """
+We make many improvements to Zulip beyond what we can share here. Check out our
+[release announcement blog post]({blog_post_12_0_url}) to learn about additional
+feature highlights in Zulip Server 12.0, and other Zulip project updates.
+"""
+        ).format(
+            blog_post_12_0_url="https://blog.zulip.com/zulip-server-12-0",
+        ),
+    ),
+]
+
+
+def get_latest_zulip_update_announcements_level() -> int:
+    latest_zulip_update_announcement = zulip_update_announcements[-1]
+    return latest_zulip_update_announcement.level
+
+
+def get_zulip_update_announcements_message_for_level(level: int) -> str:
+    zulip_update_announcement = zulip_update_announcements[level - 1]
+    return remove_single_newlines(zulip_update_announcement.message)
+
+
+def get_realms_behind_zulip_update_announcements_level(level: int) -> QuerySet[Realm]:
+    # Filter out deactivated realms. When a realm is later
+    # reactivated, send the notices it missed while it was deactivated.
+    realms = Realm.objects.filter(
+        Q(zulip_update_announcements_level__isnull=True)
+        | Q(zulip_update_announcements_level__lt=level),
+        deactivated=False,
+    ).exclude(string_id=settings.SYSTEM_BOT_REALM)
+    return realms
+
+
+def get_topic_name_for_zulip_update_announcements(realm: Realm) -> str:
+    assert realm.zulip_update_announcements_stream is not None
+
+    with override_language(realm.default_language):
+        topic_name = str(realm.ZULIP_UPDATE_ANNOUNCEMENTS_TOPIC_NAME)
+
+    if (
+        realm.zulip_update_announcements_stream.topics_policy
+        == StreamTopicsPolicyEnum.empty_topic_only.value
+    ):
+        topic_name = ""
+
+    return topic_name
+
+
+def internal_prep_group_direct_message_for_old_realm(
+    realm: Realm, sender: UserProfile
+) -> SendMessageRequest | None:
+    administrators = list(realm.get_human_admin_users())
+    if realm.zulip_update_announcements_stream is None:
+        content = """
+Zulip now supports [configuring]({organization_settings_url}) a channel where Zulip will
+send [updates]({zulip_update_announcements_help_url}) about new Zulip features.
+These notifications are currently turned off in your organization. If you configure
+a channel within one week, your organization will not miss any update messages.
+""".format(
+            zulip_update_announcements_help_url="/help/configure-automated-notices#zulip-update-announcements",
+            organization_settings_url="/#organization/organization-settings",
+        )
+    else:
+        topic_name = get_topic_name_for_zulip_update_announcements(realm)
+        content = """
+Starting tomorrow, users in your organization will receive [updates]({zulip_update_announcements_help_url})
+about new Zulip features in #**{zulip_update_announcements_stream}>{topic_name}**.
+
+If you like, you can [configure]({organization_settings_url}) a different channel for
+these updates (and [move]({move_content_another_stream_help_url}) any updates sent before the
+configuration change), or [turn this feature off]({organization_settings_url}) altogether.
+""".format(
+            zulip_update_announcements_help_url="/help/configure-automated-notices#zulip-update-announcements",
+            zulip_update_announcements_stream=realm.zulip_update_announcements_stream.name,
+            topic_name=topic_name,
+            organization_settings_url="/#organization/organization-settings",
+            move_content_another_stream_help_url="/help/move-content-to-another-channel",
+        )
+    return internal_prep_group_direct_message(
+        realm, sender, remove_single_newlines(content), recipient_users=administrators
+    )
+
+
+def get_level_none_to_initial_auditlog(realm: Realm) -> RealmAuditLog | None:
+    return RealmAuditLog.objects.filter(
+        realm=realm,
+        event_type=AuditLogEventType.REALM_PROPERTY_CHANGED,
+        extra_data__contains={
+            # Note: We're looking for the transition away from None,
+            # which usually will be to level 0, but can be to a higher
+            # initial level if the organization was imported from
+            # another chat tool.
+            RealmAuditLog.OLD_VALUE: None,
+            "property": "zulip_update_announcements_level",
+        },
+    ).first()
+
+
+def is_group_direct_message_sent_to_admins_within_days(realm: Realm, days: int) -> bool:
+    level_none_to_initial_auditlog = get_level_none_to_initial_auditlog(realm)
+    assert level_none_to_initial_auditlog is not None
+    group_direct_message_sent_on = level_none_to_initial_auditlog.event_time
+    return timezone_now() - group_direct_message_sent_on < timedelta(days=days)
+
+
+def is_realm_imported_from_other_product(realm: Realm) -> bool:
+    imported_audit_log = RealmAuditLog.objects.filter(
+        realm=realm, event_type=AuditLogEventType.REALM_IMPORTED
+    ).last()
+    if imported_audit_log is None:
+        return False
+
+    import_source = imported_audit_log.extra_data.get("import_source")
+    # Old AuditLog entries of this kind did not have import_source set. Let's just treat them
+    # like regular zulip imports.
+    return import_source is not None and import_source != "zulip"
+
+
+def internal_prep_zulip_update_announcements_stream_messages(
+    current_level: int, latest_level: int, sender: UserProfile, realm: Realm
+) -> list[SendMessageRequest | None]:
+    message_requests = []
+    stream = realm.zulip_update_announcements_stream
+    assert stream is not None
+    topic_name = get_topic_name_for_zulip_update_announcements(realm)
+
+    while current_level < latest_level:
+        content = get_zulip_update_announcements_message_for_level(level=current_level + 1)
+        message_requests.append(
+            internal_prep_stream_message(
+                sender,
+                stream,
+                topic_name,
+                content,
+            )
+        )
+        current_level += 1
+    return message_requests
+
+
+@transaction.atomic(savepoint=False)
+def send_messages_and_update_level(
+    realm: Realm,
+    new_zulip_update_announcements_level: int,
+    send_message_requests: list[SendMessageRequest | None],
+) -> None:
+    sent_message_ids = []
+    if send_message_requests:
+        sent_messages = do_send_messages(send_message_requests)
+        sent_message_ids = [sent_message.message_id for sent_message in sent_messages]
+
+    RealmAuditLog.objects.create(
+        realm=realm,
+        event_type=AuditLogEventType.REALM_PROPERTY_CHANGED,
+        event_time=timezone_now(),
+        extra_data={
+            RealmAuditLog.OLD_VALUE: realm.zulip_update_announcements_level,
+            RealmAuditLog.NEW_VALUE: new_zulip_update_announcements_level,
+            "property": "zulip_update_announcements_level",
+            "zulip_update_announcements_message_ids": sent_message_ids,
+        },
+    )
+
+    realm.zulip_update_announcements_level = new_zulip_update_announcements_level
+    realm.save(update_fields=["zulip_update_announcements_level"])
+
+
+def send_zulip_update_announcements(skip_delay: bool, progress: bool = False) -> None:
+    latest_zulip_update_announcements_level = get_latest_zulip_update_announcements_level()
+    realms = get_realms_behind_zulip_update_announcements_level(
+        level=latest_zulip_update_announcements_level
+    )
+    if len(realms) == 0:
+        return
+
+    if progress:  # nocoverage
+        print(f"Sending update announcements to {len(realms)} realms")
+    for i, realm in enumerate(realms, start=1):
+        try:
+            send_zulip_update_announcements_to_realm(realm, skip_delay)
+        except Exception:  # nocoverage
+            logging.exception("Error while sending update announcements")
+        finally:
+            if progress and i % 50 == 0:  # nocoverage
+                print(f"Processed {i}/{len(realms)} realms...")
+    if progress:  # nocoverage
+        print("Done!")
+
+
+def send_zulip_update_announcements_to_realm(realm: Realm, skip_delay: bool) -> None:
+    latest_zulip_update_announcements_level = get_latest_zulip_update_announcements_level()
+    realm_imported_from_other_product = is_realm_imported_from_other_product(realm)
+
+    # Refresh the realm from the database and check its
+    # properties, to protect against racing with another copy of
+    # ourself.
+    realm.refresh_from_db()
+    realm_zulip_update_announcements_level = realm.zulip_update_announcements_level
+    assert (
+        realm_zulip_update_announcements_level is None
+        or realm_zulip_update_announcements_level < latest_zulip_update_announcements_level
+    )
+
+    sender = get_system_bot(settings.NOTIFICATION_BOT, realm.id)
+
+    messages = []
+    new_zulip_update_announcements_level = None
+
+    if realm_zulip_update_announcements_level is None:
+        # This realm predates the zulip update announcements feature, or
+        # was imported from another product (Slack, Mattermost, etc.).
+        # Group DM the administrators to set or verify the stream for
+        # zulip update announcements.
+        group_direct_message = internal_prep_group_direct_message_for_old_realm(realm, sender)
+        messages = [group_direct_message]
+        if realm_imported_from_other_product:
+            new_zulip_update_announcements_level = latest_zulip_update_announcements_level
+        else:
+            new_zulip_update_announcements_level = 0
+    elif realm.zulip_update_announcements_stream is None:
+        # Realm misses the update messages in two cases:
+        # Case 1: New realm created, and later stream manually set to None.
+        # No group direct message is sent. Introductory message in the topic is sent.
+        # Case 2: For old realm or realm imported from other product, we wait for A WEEK
+        # after sending group DMs to let admins configure stream for zulip update announcements.
+        # After that, they miss updates until they don't configure.
+        level_none_to_initial_auditlog = get_level_none_to_initial_auditlog(realm)
+        if level_none_to_initial_auditlog is None or not (
+            timezone_now() - level_none_to_initial_auditlog.event_time < timedelta(days=7)
+        ):
+            new_zulip_update_announcements_level = latest_zulip_update_announcements_level
+    elif realm.zulip_update_announcements_stream.deactivated:  # nocoverage
+        # `zulip_update_announcements_stream` should be set to None when its channel is
+        # deactivated. If this condition occurs, there's a bug that needs investigation.
+        raise JsonableError(_("`zulip_update_announcements_stream` is unexpectedly deactivated."))
+    else:
+        # Wait for 24 hours after sending group DM to allow admins to change the
+        # stream for zulip update announcements from it's default value if desired.
+        if (
+            (realm_zulip_update_announcements_level == 0 or realm_imported_from_other_product)
+            and is_group_direct_message_sent_to_admins_within_days(realm, days=1)
+            and not skip_delay
+        ):
+            return
+
+        # Send an introductory message just before the first update message.
+        stream = realm.zulip_update_announcements_stream
+        assert stream.recipient_id is not None
+        topic_name = get_topic_name_for_zulip_update_announcements(realm)
+        topic_has_messages = messages_for_topic(realm.id, stream.recipient_id, topic_name).exists()
+
+        if not topic_has_messages:
+            content_of_introductory_message = (
+                """
+To help you learn about new features and configuration options,
+this topic will receive messages about important changes in Zulip.
+
+You can read these update messages whenever it's convenient, or
+[mute]({mute_topic_help_url}) this topic if you are not interested.
+If your organization does not want to receive these announcements,
+they can be disabled. [Learn more]({zulip_update_announcements_help_url}).
+"""
+            ).format(
+                zulip_update_announcements_help_url="/help/configure-automated-notices#zulip-update-announcements",
+                mute_topic_help_url="/help/mute-a-topic",
+            )
+            messages = [
+                internal_prep_stream_message(
+                    sender,
+                    stream,
+                    topic_name,
+                    remove_single_newlines(content_of_introductory_message),
+                )
+            ]
+
+        messages.extend(
+            internal_prep_zulip_update_announcements_stream_messages(
+                current_level=realm_zulip_update_announcements_level,
+                latest_level=latest_zulip_update_announcements_level,
+                sender=sender,
+                realm=realm,
+            )
+        )
+
+        new_zulip_update_announcements_level = latest_zulip_update_announcements_level
+
+    if new_zulip_update_announcements_level is not None:
+        send_messages_and_update_level(realm, new_zulip_update_announcements_level, messages)