FEATURE: encourage users to set chat thread titles (#26617)

This change encourages users to title their threads to make it easier for other users to join in on conversations that matter to them.

The creator of the chat thread will receive a toast notification prompting them to add a thread title when on mobile and the thread has at least 5 sent replies.

app/models/user_option.rb

@@ -291,6 +291,7 @@ end
 #  watched_precedence_over_muted        :boolean
 #  chat_separate_sidebar_mode           :integer          default(0), not null
 #  topics_unread_when_closed            :boolean          default(TRUE), not null
+#  show_thread_title_prompts            :boolean          default(TRUE), not null
 #
 # Indexes
 #

plugins/chat/app/controllers/chat/api/channel_threads_current_user_title_prompt_seen_controller.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+class Chat::Api::ChannelThreadsCurrentUserTitlePromptSeenController < Chat::ApiController
+  def update
+    with_service(Chat::MarkThreadTitlePromptSeen) do
+      on_failed_policy(:threading_enabled_for_channel) { raise Discourse::NotFound }
+      on_failed_policy(:can_view_channel) { raise Discourse::InvalidAccess }
+      on_model_not_found(:thread) { raise Discourse::NotFound }
+      on_success do
+        render_serialized(
+          result.membership,
+          Chat::BaseThreadMembershipSerializer,
+          root: "membership",
+        )
+      end
+      on_failure { render(json: failed_json, status: 422) }
+      on_failed_contract do |contract|
+        render(json: failed_json.merge(errors: contract.errors.full_messages), status: 400)
+      end
+    end
+  end
+end

plugins/chat/app/models/chat/thread.rb

@@ -42,8 +42,12 @@ module Chat
     # as the last message in this case as a fallback.
     before_create { self.last_message_id = self.original_message_id }
 
-    def add(user)
-      Chat::UserChatThreadMembership.find_or_create_by!(user: user, thread: self)
+    def add(user, notification_level: Chat::NotificationLevels.all[:tracking])
+      Chat::UserChatThreadMembership.find_or_create_by!(
+        user: user,
+        thread: self,
+        notification_level: notification_level,
+      )
     end
 
     def remove(user)

plugins/chat/app/models/chat/user_chat_thread_membership.rb

@@ -20,13 +20,14 @@ end
 #
 # Table name: user_chat_thread_memberships
 #
-#  id                   :bigint           not null, primary key
-#  user_id              :bigint           not null
-#  thread_id            :bigint           not null
-#  last_read_message_id :bigint
-#  notification_level   :integer          default("tracking"), not null
-#  created_at           :datetime         not null
-#  updated_at           :datetime         not null
+#  id                        :bigint           not null, primary key
+#  user_id                   :bigint           not null
+#  thread_id                 :bigint           not null
+#  last_read_message_id      :bigint
+#  notification_level        :integer          default("tracking"), not null
+#  thread_title_prompt_seen  :boolean          default(false), not null
+#  created_at                :datetime         not null
+#  updated_at                :datetime         not null
 #
 # Indexes
 #

plugins/chat/app/serializers/chat/base_thread_membership_serializer.rb

@@ -2,11 +2,15 @@
 
 module Chat
   class BaseThreadMembershipSerializer < ApplicationSerializer
-    attributes :notification_level, :thread_id, :last_read_message_id
+    attributes :notification_level, :thread_id, :last_read_message_id, :thread_title_prompt_seen
 
     def notification_level
       Chat::UserChatThreadMembership.notification_levels[object.notification_level] ||
         Chat::UserChatThreadMembership.notification_levels["normal"]
     end
+
+    def thread_title_prompt_seen
+      object.try(:thread_title_prompt_seen) || false
+    end
   end
 end

plugins/chat/app/services/chat/mark_thread_title_prompt_seen.rb

@@ -0,0 +1,63 @@
+# frozen_string_literal: true
+
+module Chat
+  # Marks the thread title prompt as seen for a specific user/thread
+  # Note: if the thread does not exist, it adds the user as a member of the thread
+  # before setting the thread title prompt.
+  #
+  # @example
+  # Chat::MarkThreadTitlePromptSeen.call(
+  #   thread_id: 88,
+  #   channel_id: 2,
+  #   guardian: guardian,
+  # )
+  #
+  class MarkThreadTitlePromptSeen
+    include Service::Base
+
+    # @!method call(thread_id:, channel_id:, guardian:)
+    #   @param [Integer] thread_id
+    #   @param [Integer] channel_id
+    #   @param [Guardian] guardian
+    #   @return [Service::Base::Context]
+
+    contract
+    model :thread
+    policy :threading_enabled_for_channel
+    policy :can_view_channel
+    transaction { step :create_or_update_membership }
+
+    # @!visibility private
+    class Contract
+      attribute :thread_id, :integer
+      attribute :channel_id, :integer
+
+      validates :thread_id, :channel_id, presence: true
+    end
+
+    private
+
+    def fetch_thread(contract:)
+      Chat::Thread.find_by(id: contract.thread_id, channel_id: contract.channel_id)
+    end
+
+    def can_view_channel(guardian:, thread:)
+      guardian.can_preview_chat_channel?(thread.channel)
+    end
+
+    def threading_enabled_for_channel(thread:)
+      thread.channel.threading_enabled
+    end
+
+    def create_or_update_membership(thread:, guardian:, contract:)
+      membership = thread.membership_for(guardian.user)
+      membership =
+        thread.add(
+          guardian.user,
+          notification_level: Chat::NotificationLevels.all[:normal],
+        ) if !membership
+      membership.update!(thread_title_prompt_seen: true)
+      context.membership = membership
+    end
+  end
+end

plugins/chat/assets/javascripts/discourse/components/chat-thread-title-prompt.js

@@ -0,0 +1,114 @@
+import Component from "@glimmer/component";
+import { action } from "@ember/object";
+import { next } from "@ember/runloop";
+import { service } from "@ember/service";
+import I18n from "I18n";
+import ThreadSettingsModal from "discourse/plugins/chat/discourse/components/chat/modal/thread-settings";
+import { THREAD_TITLE_PROMPT_THRESHOLD } from "discourse/plugins/chat/discourse/lib/chat-constants";
+import UserChatThreadMembership from "discourse/plugins/chat/discourse/models/user-chat-thread-membership";
+
+export default class ShowThreadTitlePrompt extends Component {
+  @service chatApi;
+  @service modal;
+  @service toasts;
+  @service currentUser;
+  @service site;
+
+  toastText = {
+    title: I18n.t("chat.thread_title_toast.title"),
+    message: I18n.t("chat.thread_title_toast.message"),
+    dismissLabel: I18n.t("chat.thread_title_toast.dismiss_action"),
+    primaryLabel: I18n.t("chat.thread_title_toast.primary_action"),
+  };
+
+  constructor() {
+    super(...arguments);
+
+    next(() => {
+      if (this.canShowToast) {
+        this.show();
+        this.updateThreadTitlePrompt();
+      }
+    });
+  }
+
+  get membership() {
+    return this.args.thread.currentUserMembership;
+  }
+
+  @action
+  async updateThreadTitlePrompt() {
+    try {
+      const result = await this.chatApi.updateCurrentUserThreadTitlePrompt(
+        this.args.thread.channel.id,
+        this.args.thread.id
+      );
+
+      this.args.thread.currentUserMembership = UserChatThreadMembership.create(
+        result.membership
+      );
+    } catch (e) {
+      // eslint-disable-next-line no-console
+      console.log("Couldn't save thread title prompt status", e);
+
+      if (this.membership) {
+        this.membership.threadTitlePromptSeen = false;
+      }
+    }
+  }
+
+  @action
+  disableFutureThreadTitlePrompts() {
+    this.currentUser.set("user_option.show_thread_title_prompts", false);
+    this.currentUser.save();
+  }
+
+  get canShowToast() {
+    if (
+      this.site.desktopView ||
+      (this.args.thread.user_id !== this.currentUser.id &&
+        !this.currentUser.admin)
+    ) {
+      return false;
+    }
+    const titleNotSet = this.args.thread.title === null;
+    const hasReplies =
+      this.args.thread.replyCount >= THREAD_TITLE_PROMPT_THRESHOLD;
+    const showPrompts = this.currentUser.user_option.show_thread_title_prompts;
+    const promptNotSeen = !this.membership?.threadTitlePromptSeen;
+    return titleNotSet && hasReplies && showPrompts && promptNotSeen;
+  }
+
+  show() {
+    this.toasts.default({
+      duration: 5000,
+      showProgressBar: true,
+      class: "thread-toast",
+      data: {
+        title: this.toastText.title,
+        message: this.toastText.message,
+        actions: [
+          {
+            label: this.toastText.dismissLabel,
+            class: "btn-link toast-hide",
+            action: (toast) => {
+              this.disableFutureThreadTitlePrompts();
+              toast.close();
+            },
+          },
+          {
+            label: this.toastText.primaryLabel,
+            class: "btn-primary toast-action",
+            action: (toast) => {
+              this.modal.show(ThreadSettingsModal, {
+                model: this.args.thread,
+              });
+
+              toast.close();
+            },
+          },
+        ],
+      },
+    });
+  }
+}

plugins/chat/assets/javascripts/discourse/components/chat-thread.gjs

@@ -12,6 +12,7 @@ import { resetIdle } from "discourse/lib/desktop-notifications";
 import { NotificationLevels } from "discourse/lib/notification-levels";
 import discourseDebounce from "discourse-common/lib/debounce";
 import { bind } from "discourse-common/utils/decorators";
+import ShowThreadTitlePrompt from "discourse/plugins/chat/discourse/components/chat-thread-title-prompt";
 import firstVisibleMessageId from "discourse/plugins/chat/discourse/helpers/first-visible-message-id";
 import ChatChannelThreadSubscriptionManager from "discourse/plugins/chat/discourse/lib/chat-channel-thread-subscription-manager";
 import {
@@ -583,6 +584,7 @@ export default class ChatThread extends Component {
       {{/if}}
 
       <ChatUploadDropZone @model={{@thread}} />
+      <ShowThreadTitlePrompt @thread={{@thread}} />
     </div>
   </template>
 }

plugins/chat/assets/javascripts/discourse/components/chat/modal/thread-settings.gjs

@@ -3,9 +3,11 @@ import { tracked } from "@glimmer/tracking";
 import { Input } from "@ember/component";
 import { action } from "@ember/object";
 import { service } from "@ember/service";
+import { htmlSafe } from "@ember/template";
 import DButton from "discourse/components/d-button";
 import DModal from "discourse/components/d-modal";
 import { popupAjaxError } from "discourse/lib/ajax-error";
+import icon from "discourse-common/helpers/d-icon";
 import i18n from "discourse-common/helpers/i18n";
 
 export default class ChatModalThreadSettings extends Component {
@@ -22,6 +24,10 @@ export default class ChatModalThreadSettings extends Component {
     return this.args.model;
   }
 
+  get threadTitleLength() {
+    return this.editedTitle.length;
+  }
+
   @action
   saveThread() {
     this.saving = true;
@@ -45,18 +51,40 @@ export default class ChatModalThreadSettings extends Component {
       @closeModal={{@closeModal}}
       class="chat-modal-thread-settings"
       @inline={{@inline}}
-      @title={{i18n "chat.thread.settings"}}
+      @title={{i18n "chat.thread_title_modal.title"}}
     >
+      <:headerPrimaryAction>
+        <DButton
+          @disabled={{this.buttonDisabled}}
+          @action={{this.saveThread}}
+          @label="chat.save"
+          class="btn-transparent btn-primary"
+        />
+      </:headerPrimaryAction>
       <:body>
-        <label for="thread-title" class="thread-title-label">
-          {{i18n "chat.thread.title"}}
-        </label>
         <Input
           name="thread-title"
           class="chat-modal-thread-settings__title-input"
+          maxlength="50"
+          placeholder={{i18n "chat.thread_title_modal.input_placeholder"}}
           @type="text"
           @value={{this.editedTitle}}
         />
+        <div class="thread-title-length">
+          <span>{{this.threadTitleLength}}</span>/50
+        </div>
+
+        <div class="discourse-ai-cta">
+          <p class="discourse-ai-cta__title">{{icon "info-circle"}}
+            {{i18n "chat.thread_title_modal.discourse_ai.title"}}</p>
+          <p class="discourse-ai-cta__description">{{htmlSafe
+              (i18n
+                "chat.thread_title_modal.discourse_ai.description"
+                url="<a href='https://www.discourse.org/ai' rel='noopener noreferrer' target='_blank'>Discourse AI</a>"
+              )
+            }}
+          </p>
+        </div>
       </:body>
       <:footer>
         <DButton

plugins/chat/assets/javascripts/discourse/components/chat/navbar/title.gjs

@@ -1,4 +1,5 @@
 import { hash } from "@ember/helper";
+import DButton from "discourse/components/d-button";
 import concatClass from "discourse/helpers/concat-class";
 import icon from "discourse-common/helpers/d-icon";
 import SubTitle from "./sub-title";
@@ -8,15 +9,21 @@ const ChatNavbarTitle = <template>
     title={{@title}}
     class={{concatClass "c-navbar__title" (if @showFullTitle "full-title")}}
   >
-    {{#if (has-block)}}
-      <span class="c-navbar__title-text">{{if @icon (icon @icon)}}
-        {{@title}}</span>
-      {{yield (hash SubTitle=SubTitle)}}
+    {{#if @openThreadTitleModal}}
+      <DButton
+        class="c-navbar__title-text btn-transparent"
+        @icon={{@icon}}
+        @action={{@openThreadTitleModal}}
+        @translatedLabel={{@title}}
+      />
     {{else}}
-      <span class="c-navbar__title-text">{{if
-          @icon
-          (icon @icon)
-        }}{{@title}}</span>
+      <span class="c-navbar__title-text">
+        {{if @icon (icon @icon)}}
+        {{@title}}
+      </span>
+    {{/if}}
+    {{#if (has-block)}}
+      {{yield (hash SubTitle=SubTitle)}}
     {{/if}}
   </div>
 </template>;

plugins/chat/assets/javascripts/discourse/components/chat/thread/header.gjs

@@ -1,15 +1,18 @@
 import Component from "@glimmer/component";
 import { service } from "@ember/service";
+import noop from "discourse/helpers/noop";
 import replaceEmoji from "discourse/helpers/replace-emoji";
 import icon from "discourse-common/helpers/d-icon";
 import I18n from "discourse-i18n";
 import and from "truth-helpers/helpers/and";
+import ThreadSettingsModal from "discourse/plugins/chat/discourse/components/chat/modal/thread-settings";
 import Navbar from "discourse/plugins/chat/discourse/components/chat/navbar";
 import ChatThreadHeaderUnreadIndicator from "discourse/plugins/chat/discourse/components/chat/thread/header-unread-indicator";
 
 export default class ChatThreadHeader extends Component {
   @service currentUser;
   @service chatHistory;
+  @service modal;
   @service site;
 
   get backLink() {
@@ -59,6 +62,18 @@ export default class ChatThreadHeader extends Component {
     );
   }
 
+  get openThreadTitleModal() {
+    if (
+      this.currentUser.admin ||
+      this.currentUser.id === this.args.thread?.originalMessage?.user?.id
+    ) {
+      return () =>
+        this.modal.show(ThreadSettingsModal, { model: this.args.thread });
+    } else {
+      return noop;
+    }
+  }
+
   <template>
     <Navbar @showFullTitle={{@showFullTitle}} as |navbar|>
       {{#if (and this.channel.threadingEnabled @thread)}}
@@ -74,7 +89,10 @@ export default class ChatThreadHeader extends Component {
         </navbar.BackButton>
       {{/if}}
 
-      <navbar.Title @title={{replaceEmoji this.headerTitle}} />
+      <navbar.Title
+        @title={{replaceEmoji this.headerTitle}}
+        @openThreadTitleModal={{this.openThreadTitleModal}}
+      />
       <navbar.Actions as |action|>
         <action.ThreadTrackingDropdown @thread={{@thread}} />
         <action.ThreadSettingsButton @thread={{@thread}} />

plugins/chat/assets/javascripts/discourse/controllers/preferences-chat.js

@@ -11,6 +11,7 @@ const CHAT_ATTRS = [
   "chat_enabled",
   "only_chat_push_notifications",
   "ignore_channel_wide_mention",
+  "show_thread_title_prompts",
   "chat_sound",
   "chat_email_frequency",
   "chat_header_indicator_preference",

plugins/chat/assets/javascripts/discourse/initializers/chat-user-options.js

@@ -3,6 +3,7 @@ import { withPluginApi } from "discourse/lib/plugin-api";
 const CHAT_ENABLED_FIELD = "chat_enabled";
 const ONLY_CHAT_PUSH_NOTIFICATIONS_FIELD = "only_chat_push_notifications";
 const IGNORE_CHANNEL_WIDE_MENTION = "ignore_channel_wide_mention";
+const SHOW_THREAD_TITLE_PROMPTS = "show_thread_title_prompts";
 const CHAT_SOUND = "chat_sound";
 const CHAT_EMAIL_FREQUENCY = "chat_email_frequency";
 const CHAT_HEADER_INDICATOR_PREFERENCE = "chat_header_indicator_preference";
@@ -18,6 +19,7 @@ export default {
         api.addSaveableUserOptionField(CHAT_ENABLED_FIELD);
         api.addSaveableUserOptionField(ONLY_CHAT_PUSH_NOTIFICATIONS_FIELD);
         api.addSaveableUserOptionField(IGNORE_CHANNEL_WIDE_MENTION);
+        api.addSaveableUserOptionField(SHOW_THREAD_TITLE_PROMPTS);
         api.addSaveableUserOptionField(CHAT_SOUND);
         api.addSaveableUserOptionField(CHAT_EMAIL_FREQUENCY);
         api.addSaveableUserOptionField(CHAT_HEADER_INDICATOR_PREFERENCE);

plugins/chat/assets/javascripts/discourse/lib/chat-constants.js

@@ -2,6 +2,7 @@ export const PAST = "past";
 export const FUTURE = "future";
 export const READ_INTERVAL_MS = 1000;
 export const DEFAULT_MESSAGE_PAGE_SIZE = 50;
+export const THREAD_TITLE_PROMPT_THRESHOLD = 5;
 export const FOOTER_NAV_ROUTES = [
   "chat.direct-messages",
   "chat.channels",

plugins/chat/assets/javascripts/discourse/models/user-chat-thread-membership.js

@@ -8,10 +8,12 @@ export default class UserChatThreadMembership {
 
   @tracked lastReadMessageId = null;
   @tracked notificationLevel = null;
+  @tracked threadTitlePromptSeen = null;
 
   constructor(args = {}) {
     this.lastReadMessageId = args.last_read_message_id;
     this.notificationLevel = args.notification_level;
+    this.threadTitlePromptSeen = args.thread_title_prompt_seen;
   }
 
   get isQuiet() {

plugins/chat/assets/javascripts/discourse/services/chat-api.js

@@ -373,6 +373,18 @@ export default class ChatApi extends Service {
     );
   }
 
+  /**
+   * Update thread title prompt of current user for a thread.
+   * @param {number} channelId - The ID of the channel.
+   * @param {number} threadId - The ID of the thread.
+   * @returns {Promise}
+   */
+  updateCurrentUserThreadTitlePrompt(channelId, threadId) {
+    return this.#postRequest(
+      `/channels/${channelId}/threads/${threadId}/mark-thread-title-prompt-seen/me`
+    );
+  }
+
   /**
    * Saves a draft for the channel, which includes message contents and uploads.
    * @param {number} channelId - The ID of the channel.

plugins/chat/assets/stylesheets/mobile/chat-modal-thread-settings.scss

@@ -1,9 +1,27 @@
-.modal-chat-thread-settings {
-  .modal-inner-container {
-    width: 98%;
+.chat-modal-thread-settings {
+  .thread-title-length {
+    color: var(--primary-medium);
+    margin-bottom: 1rem;
+    text-align: right;
   }
 
-  &__title-input {
-    width: 100%;
+  .discourse-ai-cta {
+    padding: 1rem 1.25rem;
+    border-radius: 0.25rem;
+    background-color: var(--primary-very-low);
+    border: 1px solid var(--primary-low);
+    margin-top: 5rem;
+
+    p {
+      margin: 0;
+    }
+
+    &__title {
+      font-weight: bold;
+    }
+
+    &__description {
+      font-size: var(--font-down-1);
+    }
   }
 }

plugins/chat/assets/stylesheets/mobile/chat-thread.scss

@@ -7,3 +7,15 @@
     padding: 10px 10px 0 10px;
   }
 }
+
+.thread-toast {
+  .toast-hide {
+    font-size: var(--font-down-1);
+  }
+
+  .toast-action {
+    position: absolute;
+    bottom: 0;
+    right: 0;
+  }
+}

plugins/chat/assets/stylesheets/mobile/index.scss

@@ -18,6 +18,7 @@
 @import "chat-channel-settings";
 @import "chat-form";
 @import "chat-modal-new-message";
+@import "chat-modal-thread-settings";
 @import "chat-navbar";
 @import "chat-thread-list-header";
 @import "chat-user-threads";

plugins/chat/config/locales/client.en.yml

@@ -238,6 +238,9 @@ en:
       ignore_channel_wide_mention:
         title: "Ignore channel-wide mentions"
         description: "Do not send notifications for channel-wide mentions (@here and @all)"
+      show_thread_title_prompts:
+        title: "Show thread title prompts"
+        description: "Show prompts to set a title for new threads"
       open: "Open chat"
       open_full_page: "Open full-screen chat"
       close_full_page: "Close full-screen chat"
@@ -634,6 +637,17 @@ en:
         participants_other_count:
           one: "+%{count}"
           other: "+%{count}"
+      thread_title_toast:
+        title: "Set a thread title"
+        message: "Help others discover this conversation."
+        dismiss_action: "Don't show again"
+        primary_action: "Set title"
+      thread_title_modal:
+        title: "Set thread title"
+        input_placeholder: "Tell others what this conversation is about..."
+        discourse_ai:
+          title: "Generate thread titles automatically"
+          description: "Check out %{url} to learn more about this and other enhancements to your Discourse experience."
       threads:
         open: "Open Thread"
         list: "Threads"

plugins/chat/config/routes.rb

@@ -49,6 +49,8 @@ Chat::Engine.routes.draw do
     post "/channels/:channel_id/threads/:thread_id/drafts" => "channels_threads_drafts#create"
     put "/channels/:channel_id/threads/:thread_id/notifications-settings/me" =>
           "channel_threads_current_user_notifications_settings#update"
+    post "/channels/:channel_id/threads/:thread_id/mark-thread-title-prompt-seen/me" =>
+           "channel_threads_current_user_title_prompt_seen#update"
 
     # TODO (martin) Remove this when we refactor the DM channel creation to happen
     # via message creation in a different API controller.

plugins/chat/db/migrate/20240409060201_add_thread_title_prompt_to_user_chat_thread_memberships.rb

@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+class AddThreadTitlePromptToUserChatThreadMemberships < ActiveRecord::Migration[7.0]
+  def change
+    add_column :user_chat_thread_memberships,
+               :thread_title_prompt_seen,
+               :boolean,
+               default: false,
+               null: false
+  end
+end

plugins/chat/db/migrate/20240409093348_add_show_thread_title_prompts_to_user_options.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class AddShowThreadTitlePromptsToUserOptions < ActiveRecord::Migration[7.0]
+  def change
+    add_column :user_options, :show_thread_title_prompts, :boolean, default: true, null: false
+  end
+end

plugins/chat/lib/chat/user_option_extension.rb

@@ -45,6 +45,10 @@ module Chat
                   base.chat_separate_sidebar_mode,
                   prefix: "chat_separate_sidebar_mode"
       end
+
+      if !base.method_defined?(:show_thread_title_prompts?)
+        base.attribute :show_thread_title_prompts, :boolean, default: true
+      end
     end
   end
 end

plugins/chat/plugin.rb

@@ -54,6 +54,7 @@ after_initialize do
   UserUpdater::OPTION_ATTR.push(:only_chat_push_notifications)
   UserUpdater::OPTION_ATTR.push(:chat_sound)
   UserUpdater::OPTION_ATTR.push(:ignore_channel_wide_mention)
+  UserUpdater::OPTION_ATTR.push(:show_thread_title_prompts)
   UserUpdater::OPTION_ATTR.push(:chat_email_frequency)
   UserUpdater::OPTION_ATTR.push(:chat_header_indicator_preference)
   UserUpdater::OPTION_ATTR.push(:chat_separate_sidebar_mode)
@@ -251,6 +252,12 @@ after_initialize do
     object.ignore_channel_wide_mention
   end
 
+  add_to_serializer(:user_option, :show_thread_title_prompts) { object.show_thread_title_prompts }
+
+  add_to_serializer(:current_user_option, :show_thread_title_prompts) do
+    object.show_thread_title_prompts
+  end
+
   add_to_serializer(:user_option, :chat_email_frequency) { object.chat_email_frequency }
 
   add_to_serializer(:user_option, :chat_header_indicator_preference) do

plugins/chat/spec/models/user_option_spec.rb

@@ -6,4 +6,9 @@ RSpec.describe UserOption do
       expect(described_class.new.chat_separate_sidebar_mode).to eq("default")
     end
   end
+  describe "#show_thread_title_prompts" do
+    it "is present" do
+      expect(described_class.new.show_thread_title_prompts).to eq(true)
+    end
+  end
 end

plugins/chat/spec/requests/chat/api/channel_threads_current_user_notification_settings_controller_spec.rb

@@ -77,6 +77,7 @@ RSpec.describe Chat::Api::ChannelThreadsCurrentUserNotificationsSettingsControll
           "notification_level" => Chat::UserChatThreadMembership.notification_levels[:normal],
           "thread_id" => thread.id,
           "last_read_message_id" => last_reply.id,
+          "thread_title_prompt_seen" => false,
         )
       end
     end

plugins/chat/spec/requests/chat/api/channel_threads_current_user_title_prompt_seen_controller_spec.rb

@@ -0,0 +1,80 @@
+# frozen_string_literal: true
+
+RSpec.describe Chat::Api::ChannelThreadsCurrentUserTitlePromptSeenController do
+  fab!(:current_user) { Fabricate(:user) }
+  fab!(:channel_1) { Fabricate(:category_channel, threading_enabled: true) }
+  fab!(:message_1) { Fabricate(:chat_message, chat_channel: channel_1, user: current_user) }
+  fab!(:thread_1) { Fabricate(:chat_thread, channel: channel_1, original_message: message_1) }
+  fab!(:thread_reply) { Fabricate(:chat_message, thread: thread_1) }
+
+  before do
+    SiteSetting.chat_enabled = true
+    SiteSetting.chat_allowed_groups = Group::AUTO_GROUPS[:everyone]
+  end
+
+  describe "#update" do
+    context "when not signed in" do
+      it "returns 403" do
+        post "/chat/api/channels/#{channel_1.id}/threads/#{thread_1.id}/mark-thread-title-prompt-seen/me"
+        expect(response.status).to eq(403)
+      end
+    end
+
+    context "when signed in" do
+      before do
+        channel_1.add(current_user)
+        sign_in(current_user)
+      end
+
+      context "when invalid" do
+        it "returns 404 if channel id is not found" do
+          post "/chat/api/channels/-/threads/#{thread_1.id}/mark-thread-title-prompt-seen/me"
+          expect(response.status).to eq(404)
+        end
+
+        it "returns 404 if thread id is not found" do
+          post "/chat/api/channels/#{channel_1.id}/threads/-/mark-thread-title-prompt-seen/me"
+          expect(response.status).to eq(404)
+        end
+
+        it "returns 404 if channel threading is not enabled" do
+          channel_1.update!(threading_enabled: false)
+          post "/chat/api/channels/#{channel_1.id}/threads/#{thread_1.id}/mark-thread-title-prompt-seen/me"
+          expect(response.status).to eq(404)
+        end
+
+        it "returns 404 if user can’t view channel" do
+          channel = Fabricate(:private_category_channel)
+          thread = Fabricate(:chat_thread, channel: channel)
+          post "/chat/api/channels/#{channel.id}/threads/#{thread.id}/mark-thread-title-prompt-seen/me"
+
+          expect(response.status).to eq(404)
+        end
+      end
+
+      context "when valid" do
+        it "updates thread_title_prompt_seen" do
+          membership = thread_1.membership_for(current_user)
+
+          expect(membership.thread_title_prompt_seen).to eq(false)
+
+          post "/chat/api/channels/#{channel_1.id}/threads/#{thread_1.id}/mark-thread-title-prompt-seen/me"
+
+          expect(response.status).to eq(200)
+
+          expect(membership.reload.thread_title_prompt_seen).to eq(true)
+        end
+
+        it "creates a membership if none found" do
+          random_thread = Fabricate(:chat_thread, channel: channel_1)
+
+          expect do
+            post "/chat/api/channels/#{channel_1.id}/threads/#{random_thread.id}/mark-thread-title-prompt-seen/me"
+          end.to change { Chat::UserChatThreadMembership.count }.by(1)
+
+          expect(response.status).to eq(200)
+        end
+      end
+    end
+  end
+end

plugins/chat/spec/services/chat/mark_thread_title_prompt_seen_spec.rb

@@ -0,0 +1,83 @@
+# frozen_string_literal: true
+
+RSpec.describe Chat::MarkThreadTitlePromptSeen do
+  describe Chat::MarkThreadTitlePromptSeen::Contract, type: :model do
+    it { is_expected.to validate_presence_of :channel_id }
+    it { is_expected.to validate_presence_of :thread_id }
+  end
+
+  describe ".call" do
+    subject(:result) { described_class.call(params) }
+
+    fab!(:current_user) { Fabricate(:user) }
+    fab!(:channel) { Fabricate(:chat_channel, threading_enabled: true) }
+    fab!(:private_channel) do
+      Fabricate(:private_category_channel, group: Fabricate(:group), threading_enabled: true)
+    end
+    fab!(:thread) { Fabricate(:chat_thread, channel: channel) }
+    fab!(:last_reply) { Fabricate(:chat_message, thread: thread, chat_channel: channel) }
+
+    let(:guardian) { Guardian.new(current_user) }
+    let(:params) { { guardian: guardian, thread_id: thread.id, channel_id: thread.channel_id } }
+
+    before { thread.update!(last_message: last_reply) }
+
+    context "when all steps pass" do
+      it "sets the service result as successful" do
+        expect(result).to be_a_success
+      end
+
+      context "when the user is a member of the thread" do
+        fab!(:membership) { thread.add(current_user) }
+
+        it "updates the thread_title_prompt_seen" do
+          expect { result }.not_to change { Chat::UserChatThreadMembership.count }
+          expect(membership.reload.thread_title_prompt_seen).to eq(true)
+        end
+      end
+
+      context "when the user is not a member of the thread yet" do
+        it "creates the membership and updates thread_title_prompt_seen" do
+          expect { result }.to change { Chat::UserChatThreadMembership.count }.by(1)
+          expect(result.membership.thread_title_prompt_seen).to eq(true)
+        end
+      end
+    end
+
+    context "when thread_id is missing" do
+      before { params.delete(:thread_id) }
+
+      it { is_expected.to fail_a_contract }
+    end
+
+    context "when channel_id is missing" do
+      before { params.delete(:channel_id) }
+
+      it { is_expected.to fail_a_contract }
+    end
+
+    context "when thread is not found because the channel ID differs" do
+      before { params[:thread_id] = Fabricate(:chat_thread).id }
+
+      it { is_expected.to fail_to_find_a_model(:thread) }
+    end
+
+    context "when thread is not found" do
+      before { thread.destroy! }
+
+      it { is_expected.to fail_to_find_a_model(:thread) }
+    end
+
+    context "when threading is not enabled for the channel" do
+      before { channel.update!(threading_enabled: false) }
+
+      it { is_expected.to fail_a_policy(:threading_enabled_for_channel) }
+    end
+
+    context "when user cannot see channel" do
+      before { thread.update!(channel_id: private_channel.id) }
+
+      it { is_expected.to fail_a_policy(:can_view_channel) }
+    end
+  end
+end