diff --git a/app/assets/javascripts/admin/addon/controllers/admin-web-hooks-show-events.js b/app/assets/javascripts/admin/addon/controllers/admin-web-hooks-show-events.js
index 5e9dacb83b7..84b7650ff16 100644
--- a/app/assets/javascripts/admin/addon/controllers/admin-web-hooks-show-events.js
+++ b/app/assets/javascripts/admin/addon/controllers/admin-web-hooks-show-events.js
@@ -2,7 +2,7 @@ import Controller from "@ember/controller";
 import { ajax } from "discourse/lib/ajax";
 import { action } from "@ember/object";
 import { alias } from "@ember/object/computed";
-import discourseComputed, { bind } from "discourse-common/utils/decorators";
+import discourseComputed from "discourse-common/utils/decorators";
 import { popupAjaxError } from "discourse/lib/ajax-error";
 
 export default Controller.extend({
@@ -23,22 +23,24 @@ export default Controller.extend({
   subscribe() {
     this.messageBus.subscribe(
       `/web_hook_events/${this.get("model.extras.web_hook_id")}`,
-      this._addIncoming
+      (data) => {
+        if (data.event_type === "ping") {
+          this.set("pingDisabled", false);
+        }
+        this._addIncoming(data.web_hook_event_id);
+      }
     );
   },
 
   unsubscribe() {
-    this.messageBus.unsubscribe("/web_hook_events/*", this._addIncoming);
+    this.messageBus.unsubscribe("/web_hook_events/*");
   },
 
-  @bind
-  _addIncoming(data) {
-    if (data.event_type === "ping") {
-      this.set("pingDisabled", false);
-    }
+  _addIncoming(eventId) {
+    const incomingEventIds = this.incomingEventIds;
 
-    if (!this.incomingEventIds.includes(data.web_hook_event_id)) {
-      this.incomingEventIds.pushObject(data.web_hook_event_id);
+    if (!incomingEventIds.includes(eventId)) {
+      incomingEventIds.pushObject(eventId);
     }
   },
 
diff --git a/app/assets/javascripts/admin/addon/controllers/modals/admin-merge-users-progress.js b/app/assets/javascripts/admin/addon/controllers/modals/admin-merge-users-progress.js
index bdbcf2d220c..3d9248d36d5 100644
--- a/app/assets/javascripts/admin/addon/controllers/modals/admin-merge-users-progress.js
+++ b/app/assets/javascripts/admin/addon/controllers/modals/admin-merge-users-progress.js
@@ -2,33 +2,30 @@ import Controller from "@ember/controller";
 import DiscourseURL from "discourse/lib/url";
 import I18n from "I18n";
 import ModalFunctionality from "discourse/mixins/modal-functionality";
-import { bind } from "discourse-common/utils/decorators";
+import messageBus from "message-bus-client";
 
 export default Controller.extend(ModalFunctionality, {
   message: I18n.t("admin.user.merging_user"),
 
   onShow() {
-    this.messageBus.subscribe("/merge_user", this.onMessage);
+    messageBus.subscribe("/merge_user", (data) => {
+      if (data.merged) {
+        if (/^\/admin\/users\/list\//.test(location)) {
+          DiscourseURL.redirectTo(location);
+        } else {
+          DiscourseURL.redirectTo(
+            `/admin/users/${data.user.id}/${data.user.username}`
+          );
+        }
+      } else if (data.message) {
+        this.set("message", data.message);
+      } else if (data.failed) {
+        this.set("message", I18n.t("admin.user.merge_failed"));
+      }
+    });
   },
 
   onClose() {
-    this.messageBus.unsubscribe("/merge_user", this.onMessage);
-  },
-
-  @bind
-  onMessage(data) {
-    if (data.merged) {
-      if (/^\/admin\/users\/list\//.test(location)) {
-        DiscourseURL.redirectTo(location);
-      } else {
-        DiscourseURL.redirectTo(
-          `/admin/users/${data.user.id}/${data.user.username}`
-        );
-      }
-    } else if (data.message) {
-      this.set("message", data.message);
-    } else if (data.failed) {
-      this.set("message", I18n.t("admin.user.merge_failed"));
-    }
+    this.messageBus.unsubscribe("/merge_user");
   },
 });
diff --git a/app/assets/javascripts/admin/addon/routes/admin-backups-index.js b/app/assets/javascripts/admin/addon/routes/admin-backups-index.js
index 1f7ea93a693..cb05c26580f 100644
--- a/app/assets/javascripts/admin/addon/routes/admin-backups-index.js
+++ b/app/assets/javascripts/admin/addon/routes/admin-backups-index.js
@@ -1,14 +1,14 @@
 import Backup from "admin/models/backup";
 import Route from "@ember/routing/route";
-import { bind } from "discourse-common/utils/decorators";
 
 export default Route.extend({
   activate() {
-    this.messageBus.subscribe("/admin/backups", this.onMessage);
-  },
-
-  deactivate() {
-    this.messageBus.unsubscribe("/admin/backups", this.onMessage);
+    this.messageBus.subscribe("/admin/backups", (backups) =>
+      this.controller.set(
+        "model",
+        backups.map((backup) => Backup.create(backup))
+      )
+    );
   },
 
   model() {
@@ -17,11 +17,7 @@ export default Route.extend({
     );
   },
 
-  @bind
-  onMessage(backups) {
-    this.controller.set(
-      "model",
-      backups.map((backup) => Backup.create(backup))
-    );
+  deactivate() {
+    this.messageBus.unsubscribe("/admin/backups");
   },
 });
diff --git a/app/assets/javascripts/admin/addon/routes/admin-backups.js b/app/assets/javascripts/admin/addon/routes/admin-backups.js
index 1379a097544..c78ef4ca1cf 100644
--- a/app/assets/javascripts/admin/addon/routes/admin-backups.js
+++ b/app/assets/javascripts/admin/addon/routes/admin-backups.js
@@ -10,19 +10,46 @@ import { extractError } from "discourse/lib/ajax-error";
 import getURL from "discourse-common/lib/get-url";
 import showModal from "discourse/lib/show-modal";
 import { inject as service } from "@ember/service";
-import { bind } from "discourse-common/utils/decorators";
-
 const LOG_CHANNEL = "/admin/backups/logs";
 
 export default DiscourseRoute.extend({
   dialog: service(),
 
   activate() {
-    this.messageBus.subscribe(LOG_CHANNEL, this.onMessage);
-  },
-
-  deactivate() {
-    this.messageBus.unsubscribe(LOG_CHANNEL, this.onMessage);
+    this.messageBus.subscribe(LOG_CHANNEL, (log) => {
+      if (log.message === "[STARTED]") {
+        User.currentProp("hideReadOnlyAlert", true);
+        this.controllerFor("adminBackups").set(
+          "model.isOperationRunning",
+          true
+        );
+        this.controllerFor("adminBackupsLogs").get("logs").clear();
+      } else if (log.message === "[FAILED]") {
+        this.controllerFor("adminBackups").set(
+          "model.isOperationRunning",
+          false
+        );
+        this.dialog.alert(
+          I18n.t("admin.backups.operations.failed", {
+            operation: log.operation,
+          })
+        );
+      } else if (log.message === "[SUCCESS]") {
+        User.currentProp("hideReadOnlyAlert", false);
+        this.controllerFor("adminBackups").set(
+          "model.isOperationRunning",
+          false
+        );
+        if (log.operation === "restore") {
+          // redirect to homepage when the restore is done (session might be lost)
+          window.location = getURL("/");
+        }
+      } else {
+        this.controllerFor("adminBackupsLogs")
+          .get("logs")
+          .pushObject(EmberObject.create(log));
+      }
+    });
   },
 
   model() {
@@ -37,31 +64,8 @@ export default DiscourseRoute.extend({
     );
   },
 
-  @bind
-  onMessage(log) {
-    if (log.message === "[STARTED]") {
-      User.currentProp("hideReadOnlyAlert", true);
-      this.controllerFor("adminBackups").set("model.isOperationRunning", true);
-      this.controllerFor("adminBackupsLogs").get("logs").clear();
-    } else if (log.message === "[FAILED]") {
-      this.controllerFor("adminBackups").set("model.isOperationRunning", false);
-      this.dialog.alert(
-        I18n.t("admin.backups.operations.failed", {
-          operation: log.operation,
-        })
-      );
-    } else if (log.message === "[SUCCESS]") {
-      User.currentProp("hideReadOnlyAlert", false);
-      this.controllerFor("adminBackups").set("model.isOperationRunning", false);
-      if (log.operation === "restore") {
-        // redirect to homepage when the restore is done (session might be lost)
-        window.location = getURL("/");
-      }
-    } else {
-      this.controllerFor("adminBackupsLogs")
-        .get("logs")
-        .pushObject(EmberObject.create(log));
-    }
+  deactivate() {
+    this.messageBus.unsubscribe(LOG_CHANNEL);
   },
 
   actions: {
diff --git a/app/assets/javascripts/discourse/app/components/basic-topic-list.js b/app/assets/javascripts/discourse/app/components/basic-topic-list.js
index b7839ddf478..ca8fae33180 100644
--- a/app/assets/javascripts/discourse/app/components/basic-topic-list.js
+++ b/app/assets/javascripts/discourse/app/components/basic-topic-list.js
@@ -1,8 +1,5 @@
 import { alias, not } from "@ember/object/computed";
-import discourseComputed, {
-  bind,
-  observes,
-} from "discourse-common/utils/decorators";
+import discourseComputed, { observes } from "discourse-common/utils/decorators";
 import Component from "@ember/component";
 
 export default Component.extend({
@@ -43,11 +40,18 @@ export default Component.extend({
     this._super(...arguments);
 
     this.topics.forEach((topic) => {
-      if (typeof topic.unread_by_group_member !== "undefined") {
-        this.messageBus.subscribe(
-          `/private-messages/unread-indicator/${topic.id}`,
-          this.onMessage
-        );
+      const includeUnreadIndicator =
+        typeof topic.unread_by_group_member !== "undefined";
+
+      if (includeUnreadIndicator) {
+        const unreadIndicatorChannel = `/private-messages/unread-indicator/${topic.id}`;
+        this.messageBus.subscribe(unreadIndicatorChannel, (data) => {
+          const nodeClassList = document.querySelector(
+            `.indicator-topic-${data.topic_id}`
+          ).classList;
+
+          nodeClassList.toggle("read", !data.show_indicator);
+        });
       }
     });
   },
@@ -55,19 +59,15 @@ export default Component.extend({
   willDestroyElement() {
     this._super(...arguments);
 
-    this.messageBus.unsubscribe(
-      "/private-messages/unread-indicator/*",
-      this.onMessage
-    );
-  },
+    this.topics.forEach((topic) => {
+      const includeUnreadIndicator =
+        typeof topic.unread_by_group_member !== "undefined";
 
-  @bind
-  onMessage(data) {
-    const nodeClassList = document.querySelector(
-      `.indicator-topic-${data.topic_id}`
-    ).classList;
-
-    nodeClassList.toggle("read", !data.show_indicator);
+      if (includeUnreadIndicator) {
+        const unreadIndicatorChannel = `/private-messages/unread-indicator/${topic.id}`;
+        this.messageBus.unsubscribe(unreadIndicatorChannel);
+      }
+    });
   },
 
   @discourseComputed("topics")
diff --git a/app/assets/javascripts/discourse/app/components/software-update-prompt.js b/app/assets/javascripts/discourse/app/components/software-update-prompt.js
index 21abaa87bce..6d32dd77e53 100644
--- a/app/assets/javascripts/discourse/app/components/software-update-prompt.js
+++ b/app/assets/javascripts/discourse/app/components/software-update-prompt.js
@@ -1,7 +1,7 @@
 import getURL from "discourse-common/lib/get-url";
 import { cancel } from "@ember/runloop";
 import discourseLater from "discourse-common/lib/later";
-import discourseComputed, { bind, on } from "discourse-common/utils/decorators";
+import discourseComputed, { on } from "discourse-common/utils/decorators";
 import Component from "@ember/component";
 import { action } from "@ember/object";
 import { isTesting } from "discourse-common/config/environment";
@@ -13,49 +13,36 @@ export default Component.extend({
   animatePrompt: false,
   _timeoutHandler: null,
 
-  init() {
-    this._super(...arguments);
-
-    this.messageBus.subscribe("/refresh_client", this.onRefresh);
-    this.messageBus.subscribe("/global/asset-version", this.onAsset);
-  },
-
-  willDestroy() {
-    this._super(...arguments);
-
-    this.messageBus.unsubscribe("/refresh_client", this.onRefresh);
-    this.messageBus.unsubscribe("/global/asset-version", this.onAsset);
-  },
-
-  @bind
-  onRefresh() {
-    this.session.requiresRefresh = true;
-  },
-
-  @bind
-  onAsset(version) {
-    if (this.session.assetVersion !== version) {
-      this.session.requiresRefresh = true;
-    }
-
-    if (!this._timeoutHandler && this.session.requiresRefresh) {
-      if (isTesting()) {
-        this.updatePromptState(true);
-      } else {
-        // Since we can do this transparently for people browsing the forum
-        // hold back the message 24 hours.
-        this._timeoutHandler = discourseLater(() => {
-          this.updatePromptState(true);
-        }, 1000 * 60 * 24 * 60);
-      }
-    }
-  },
-
   @discourseComputed
   rootUrl() {
     return getURL("/");
   },
 
+  @on("init")
+  initSubscriptions() {
+    this.messageBus.subscribe("/refresh_client", () => {
+      this.session.requiresRefresh = true;
+    });
+
+    this.messageBus.subscribe("/global/asset-version", (version) => {
+      if (this.session.assetVersion !== version) {
+        this.session.requiresRefresh = true;
+      }
+
+      if (!this._timeoutHandler && this.session.requiresRefresh) {
+        if (isTesting()) {
+          this.updatePromptState(true);
+        } else {
+          // Since we can do this transparently for people browsing the forum
+          // hold back the message 24 hours.
+          this._timeoutHandler = discourseLater(() => {
+            this.updatePromptState(true);
+          }, 1000 * 60 * 24 * 60);
+        }
+      }
+    });
+  },
+
   updatePromptState(value) {
     // when adding the message, we inject the HTML then add the animation
     // when dismissing, things need to happen in the opposite order
diff --git a/app/assets/javascripts/discourse/app/components/topic-list-item.js b/app/assets/javascripts/discourse/app/components/topic-list-item.js
index 16247e89c85..2d6ce3e18fd 100644
--- a/app/assets/javascripts/discourse/app/components/topic-list-item.js
+++ b/app/assets/javascripts/discourse/app/components/topic-list-item.js
@@ -77,7 +77,13 @@ export default Component.extend({
     this._super(...arguments);
 
     if (this.includeUnreadIndicator) {
-      this.messageBus.subscribe(this.unreadIndicatorChannel, this.onMessage);
+      this.messageBus.subscribe(this.unreadIndicatorChannel, (data) => {
+        const nodeClassList = document.querySelector(
+          `.indicator-topic-${data.topic_id}`
+        ).classList;
+
+        nodeClassList.toggle("read", !data.show_indicator);
+      });
     }
 
     schedule("afterRender", () => {
@@ -95,8 +101,9 @@ export default Component.extend({
   willDestroyElement() {
     this._super(...arguments);
 
-    this.messageBus.unsubscribe(this.unreadIndicatorChannel, this.onMessage);
-
+    if (this.includeUnreadIndicator) {
+      this.messageBus.unsubscribe(this.unreadIndicatorChannel);
+    }
     if (this._shouldFocusLastVisited()) {
       const title = this._titleElement();
       if (title) {
@@ -106,15 +113,6 @@ export default Component.extend({
     }
   },
 
-  @bind
-  onMessage(data) {
-    const nodeClassList = document.querySelector(
-      `.indicator-topic-${data.topic_id}`
-    ).classList;
-
-    nodeClassList.toggle("read", !data.show_indicator);
-  },
-
   @discourseComputed("topic.id")
   unreadIndicatorChannel(topicId) {
     return `/private-messages/unread-indicator/${topicId}`;
diff --git a/app/assets/javascripts/discourse/app/controllers/topic.js b/app/assets/javascripts/discourse/app/controllers/topic.js
index 7018e62431d..eca4aca13dd 100644
--- a/app/assets/javascripts/discourse/app/controllers/topic.js
+++ b/app/assets/javascripts/discourse/app/controllers/topic.js
@@ -2,10 +2,7 @@ import Category from "discourse/models/category";
 import Controller, { inject as controller } from "@ember/controller";
 import DiscourseURL, { userPath } from "discourse/lib/url";
 import { alias, and, not, or } from "@ember/object/computed";
-import discourseComputed, {
-  bind,
-  observes,
-} from "discourse-common/utils/decorators";
+import discourseComputed, { observes } from "discourse-common/utils/decorators";
 import { isEmpty, isPresent } from "@ember/utils";
 import { next, schedule } from "@ember/runloop";
 import discourseLater from "discourse-common/lib/later";
@@ -1602,9 +1599,157 @@ export default Controller.extend(bufferedProperty("model"), {
   subscribe() {
     this.unsubscribe();
 
+    const refresh = (args) =>
+      this.appEvents.trigger("post-stream:refresh", args);
+
     this.messageBus.subscribe(
       `/topic/${this.get("model.id")}`,
-      this.onMessage,
+      (data) => {
+        const topic = this.model;
+
+        if (isPresent(data.notification_level_change)) {
+          topic.set(
+            "details.notification_level",
+            data.notification_level_change
+          );
+          topic.set(
+            "details.notifications_reason_id",
+            data.notifications_reason_id
+          );
+          return;
+        }
+
+        const postStream = this.get("model.postStream");
+
+        if (data.reload_topic) {
+          topic.reload().then(() => {
+            this.send("postChangedRoute", topic.get("post_number") || 1);
+            this.appEvents.trigger("header:update-topic", topic);
+            if (data.refresh_stream) {
+              postStream.refresh();
+            }
+          });
+
+          return;
+        }
+
+        switch (data.type) {
+          case "acted":
+            postStream
+              .triggerChangedPost(data.id, data.updated_at, {
+                preserveCooked: true,
+              })
+              .then(() => refresh({ id: data.id, refreshLikes: true }));
+            break;
+          case "read": {
+            postStream
+              .triggerReadPost(data.id, data.readers_count)
+              .then(() => refresh({ id: data.id, refreshLikes: true }));
+            break;
+          }
+          case "liked":
+          case "unliked": {
+            postStream
+              .triggerLikedPost(
+                data.id,
+                data.likes_count,
+                data.user_id,
+                data.type
+              )
+              .then(() => refresh({ id: data.id, refreshLikes: true }));
+            break;
+          }
+          case "revised":
+          case "rebaked": {
+            postStream
+              .triggerChangedPost(data.id, data.updated_at)
+              .then(() => refresh({ id: data.id }));
+            break;
+          }
+          case "deleted": {
+            postStream
+              .triggerDeletedPost(data.id)
+              .then(() => refresh({ id: data.id }));
+            break;
+          }
+          case "destroyed": {
+            postStream
+              .triggerDestroyedPost(data.id)
+              .then(() => refresh({ id: data.id }));
+            break;
+          }
+          case "recovered": {
+            postStream
+              .triggerRecoveredPost(data.id)
+              .then(() => refresh({ id: data.id }));
+            break;
+          }
+          case "created": {
+            this._newPostsInStream.push(data.id);
+
+            this.retryOnRateLimit(RETRIES_ON_RATE_LIMIT, () => {
+              const postIds = this._newPostsInStream;
+              this._newPostsInStream = [];
+
+              return postStream
+                .triggerNewPostsInStream(postIds, { background: true })
+                .then(() => refresh())
+                .catch((e) => {
+                  this._newPostsInStream = postIds.concat(
+                    this._newPostsInStream
+                  );
+                  throw e;
+                });
+            });
+
+            if (this.get("currentUser.id") !== data.user_id) {
+              this.documentTitle.incrementBackgroundContextCount();
+            }
+            break;
+          }
+          case "move_to_inbox": {
+            topic.set("message_archived", false);
+            break;
+          }
+          case "archived": {
+            topic.set("message_archived", true);
+            break;
+          }
+          case "stats": {
+            let updateStream = false;
+            ["last_posted_at", "like_count", "posts_count"].forEach(
+              (property) => {
+                const value = data[property];
+                if (typeof value !== "undefined") {
+                  topic.set(property, value);
+                  updateStream = true;
+                }
+              }
+            );
+
+            if (data["last_poster"]) {
+              topic.details.set("last_poster", data["last_poster"]);
+              updateStream = true;
+            }
+
+            if (updateStream) {
+              postStream
+                .triggerChangedTopicStats()
+                .then((firstPostId) => refresh({ id: firstPostId }));
+            }
+            break;
+          }
+          default: {
+            let callback = customPostMessageCallbacks[data.type];
+            if (callback) {
+              callback(this, data);
+            } else {
+              // eslint-disable-next-line no-console
+              console.warn("unknown topic bus message type", data);
+            }
+          }
+        }
+      },
       this.get("model.message_bus_last_id")
     );
   },
@@ -1614,148 +1759,9 @@ export default Controller.extend(bufferedProperty("model"), {
     if (!this.get("model.id")) {
       return;
     }
-
     this.messageBus.unsubscribe("/topic/*");
   },
 
-  @bind
-  onMessage(data) {
-    const topic = this.model;
-    const refresh = (args) =>
-      this.appEvents.trigger("post-stream:refresh", args);
-
-    if (isPresent(data.notification_level_change)) {
-      topic.set("details.notification_level", data.notification_level_change);
-      topic.set(
-        "details.notifications_reason_id",
-        data.notifications_reason_id
-      );
-      return;
-    }
-
-    const postStream = this.get("model.postStream");
-
-    if (data.reload_topic) {
-      topic.reload().then(() => {
-        this.send("postChangedRoute", topic.get("post_number") || 1);
-        this.appEvents.trigger("header:update-topic", topic);
-        if (data.refresh_stream) {
-          postStream.refresh();
-        }
-      });
-
-      return;
-    }
-
-    switch (data.type) {
-      case "acted":
-        postStream
-          .triggerChangedPost(data.id, data.updated_at, {
-            preserveCooked: true,
-          })
-          .then(() => refresh({ id: data.id, refreshLikes: true }));
-        break;
-      case "read": {
-        postStream
-          .triggerReadPost(data.id, data.readers_count)
-          .then(() => refresh({ id: data.id, refreshLikes: true }));
-        break;
-      }
-      case "liked":
-      case "unliked": {
-        postStream
-          .triggerLikedPost(data.id, data.likes_count, data.user_id, data.type)
-          .then(() => refresh({ id: data.id, refreshLikes: true }));
-        break;
-      }
-      case "revised":
-      case "rebaked": {
-        postStream
-          .triggerChangedPost(data.id, data.updated_at)
-          .then(() => refresh({ id: data.id }));
-        break;
-      }
-      case "deleted": {
-        postStream
-          .triggerDeletedPost(data.id)
-          .then(() => refresh({ id: data.id }));
-        break;
-      }
-      case "destroyed": {
-        postStream
-          .triggerDestroyedPost(data.id)
-          .then(() => refresh({ id: data.id }));
-        break;
-      }
-      case "recovered": {
-        postStream
-          .triggerRecoveredPost(data.id)
-          .then(() => refresh({ id: data.id }));
-        break;
-      }
-      case "created": {
-        this._newPostsInStream.push(data.id);
-
-        this.retryOnRateLimit(RETRIES_ON_RATE_LIMIT, () => {
-          const postIds = this._newPostsInStream;
-          this._newPostsInStream = [];
-
-          return postStream
-            .triggerNewPostsInStream(postIds, { background: true })
-            .then(() => refresh())
-            .catch((e) => {
-              this._newPostsInStream = postIds.concat(this._newPostsInStream);
-              throw e;
-            });
-        });
-
-        if (this.get("currentUser.id") !== data.user_id) {
-          this.documentTitle.incrementBackgroundContextCount();
-        }
-        break;
-      }
-      case "move_to_inbox": {
-        topic.set("message_archived", false);
-        break;
-      }
-      case "archived": {
-        topic.set("message_archived", true);
-        break;
-      }
-      case "stats": {
-        let updateStream = false;
-        ["last_posted_at", "like_count", "posts_count"].forEach((property) => {
-          const value = data[property];
-          if (typeof value !== "undefined") {
-            topic.set(property, value);
-            updateStream = true;
-          }
-        });
-
-        if (data["last_poster"]) {
-          topic.details.set("last_poster", data["last_poster"]);
-          updateStream = true;
-        }
-
-        if (updateStream) {
-          postStream
-            .triggerChangedTopicStats()
-            .then((firstPostId) => refresh({ id: firstPostId }));
-        }
-        break;
-      }
-      default: {
-        let callback = customPostMessageCallbacks[data.type];
-        if (callback) {
-          callback(this, data);
-        } else {
-          // eslint-disable-next-line no-console
-          console.warn("unknown topic bus message type", data);
-        }
-      }
-    }
-  },
-
   reply() {
     this.replyToPost();
   },
diff --git a/app/assets/javascripts/discourse/app/initializers/banner.js b/app/assets/javascripts/discourse/app/initializers/banner.js
index 09859d7ccbf..f766003b4b1 100644
--- a/app/assets/javascripts/discourse/app/initializers/banner.js
+++ b/app/assets/javascripts/discourse/app/initializers/banner.js
@@ -1,5 +1,4 @@
 import EmberObject from "@ember/object";
-import { bind } from "discourse-common/utils/decorators";
 import PreloadStore from "discourse/lib/preload-store";
 
 export default {
@@ -7,21 +6,14 @@ export default {
   after: "message-bus",
 
   initialize(container) {
-    this.site = container.lookup("service:site");
-    this.messageBus = container.lookup("service:message-bus");
-
+    const site = container.lookup("service:site");
     const banner = EmberObject.create(PreloadStore.get("banner") || {});
-    this.site.set("banner", banner);
+    const messageBus = container.lookup("service:message-bus");
 
-    this.messageBus.subscribe("/site/banner", this.onMessage);
-  },
+    site.set("banner", banner);
 
-  teardown() {
-    this.messageBus.unsubscribe("/site/banner", this.onMessage);
-  },
-
-  @bind
-  onMessage(data = {}) {
-    this.site.set("banner", EmberObject.create(data));
+    messageBus.subscribe("/site/banner", (data) => {
+      site.set("banner", EmberObject.create(data || {}));
+    });
   },
 };
diff --git a/app/assets/javascripts/discourse/app/initializers/live-development.js b/app/assets/javascripts/discourse/app/initializers/live-development.js
index 71c9d324998..65be3e36377 100644
--- a/app/assets/javascripts/discourse/app/initializers/live-development.js
+++ b/app/assets/javascripts/discourse/app/initializers/live-development.js
@@ -1,14 +1,13 @@
 import DiscourseURL from "discourse/lib/url";
 import { isDevelopment } from "discourse-common/config/environment";
 import discourseLater from "discourse-common/lib/later";
-import { bind } from "discourse-common/utils/decorators";
 
 //  Use the message bus for live reloading of components for faster development.
 export default {
   name: "live-development",
 
   initialize(container) {
-    this.messageBus = container.lookup("service:message-bus");
+    const messageBus = container.lookup("service:message-bus");
     const session = container.lookup("service:session");
 
     // Preserve preview_theme_id=## and pp=async-flamegraph parameters across pages
@@ -39,46 +38,37 @@ export default {
     }
 
     // Observe file changes
-    this.messageBus.subscribe(
+    messageBus.subscribe(
       "/file-change",
-      this.onFileChange,
+      (data) => {
+        data.forEach((me) => {
+          if (me === "refresh") {
+            // Refresh if necessary
+            document.location.reload(true);
+          } else if (me.new_href && me.target) {
+            const link_target = !!me.theme_id
+              ? `[data-target='${me.target}'][data-theme-id='${me.theme_id}']`
+              : `[data-target='${me.target}']`;
+
+            const links = document.querySelectorAll(`link${link_target}`);
+            if (links.length > 0) {
+              const lastLink = links[links.length - 1];
+              // this check is useful when message-bus has multiple file updates
+              // it avoids the browser doing a lot of work for nothing
+              // should the filenames be unchanged
+              if (
+                lastLink.href.split("/").pop() !== me.new_href.split("/").pop()
+              ) {
+                this.refreshCSS(lastLink, me.new_href);
+              }
+            }
+          }
+        });
+      },
       session.mbLastFileChangeId
     );
   },
 
-  teardown() {
-    this.messageBus.unsubscribe("/file-change", this.onFileChange);
-  },
-
-  @bind
-  onFileChange(data) {
-    data.forEach((me) => {
-      if (me === "refresh") {
-        // Refresh if necessary
-        document.location.reload(true);
-      } else if (me.new_href && me.target) {
-        let query = `link[data-target='${me.target}']`;
-
-        if (me.theme_id) {
-          query += `[data-theme-id='${me.theme_id}']`;
-        }
-
-        const links = document.querySelectorAll(query);
-
-        if (links.length > 0) {
-          const lastLink = links[links.length - 1];
-
-          // this check is useful when message-bus has multiple file updates
-          // it avoids the browser doing a lot of work for nothing
-          // should the filenames be unchanged
-          if (lastLink.href.split("/").pop() !== me.new_href.split("/").pop()) {
-            this.refreshCSS(lastLink, me.new_href);
-          }
-        }
-      }
-    });
-  },
-
   refreshCSS(node, newHref) {
     const reloaded = node.cloneNode(true);
     reloaded.href = newHref;
diff --git a/app/assets/javascripts/discourse/app/initializers/logout.js b/app/assets/javascripts/discourse/app/initializers/logout.js
index ed9ca4e5f38..70eb8068da1 100644
--- a/app/assets/javascripts/discourse/app/initializers/logout.js
+++ b/app/assets/javascripts/discourse/app/initializers/logout.js
@@ -1,43 +1,35 @@
 import I18n from "I18n";
 import logout from "discourse/lib/logout";
-import { bind } from "discourse-common/utils/decorators";
 
 let _showingLogout = false;
 
-// Subscribe to "logout" change events via the Message Bus
+//  Subscribe to "logout" change events via the Message Bus
 export default {
   name: "logout",
   after: "message-bus",
 
   initialize(container) {
-    this.messageBus = container.lookup("service:message-bus");
-    this.dialog = container.lookup("service:dialog");
+    const messageBus = container.lookup("service:message-bus"),
+      dialog = container.lookup("service:dialog");
 
-    if (!this.messageBus) {
+    if (!messageBus) {
       return;
     }
 
-    this.messageBus.subscribe("/logout", this.onMessage);
-  },
+    messageBus.subscribe("/logout", function () {
+      if (!_showingLogout) {
+        _showingLogout = true;
 
-  teardown() {
-    this.messageBus.unsubscribe("/logout", this.onMessage);
-  },
+        dialog.alert({
+          message: I18n.t("logout"),
+          confirmButtonLabel: "home",
+          didConfirm: logout,
+          didCancel: logout,
+          shouldDisplayCancel: false,
+        });
+      }
 
-  @bind
-  onMessage() {
-    if (_showingLogout) {
-      return;
-    }
-
-    _showingLogout = true;
-
-    this.dialog.alert({
-      message: I18n.t("logout"),
-      confirmButtonLabel: "home",
-      didConfirm: logout,
-      didCancel: logout,
-      shouldDisplayCancel: false,
+      _showingLogout = true;
     });
   },
 };
diff --git a/app/assets/javascripts/discourse/app/initializers/read-only.js b/app/assets/javascripts/discourse/app/initializers/read-only.js
index 8d322350b75..7ab4ddb9a3f 100644
--- a/app/assets/javascripts/discourse/app/initializers/read-only.js
+++ b/app/assets/javascripts/discourse/app/initializers/read-only.js
@@ -1,23 +1,13 @@
-import { bind } from "discourse-common/utils/decorators";
-
 // Subscribe to "read-only" status change events via the Message Bus
 export default {
   name: "read-only",
   after: "message-bus",
 
   initialize(container) {
-    this.messageBus = container.lookup("service:message-bus");
-    this.site = container.lookup("service:site");
-
-    this.messageBus.subscribe("/site/read-only", this.onMessage);
-  },
-
-  teardown() {
-    this.messageBus.unsubscribe("/site/read-only", this.onMessage);
-  },
-
-  @bind
-  onMessage(enabled) {
-    this.site.set("isReadOnly", enabled);
+    const messageBus = container.lookup("service:message-bus");
+    const site = container.lookup("service:site");
+    messageBus.subscribe("/site/read-only", (enabled) => {
+      site.set("isReadOnly", enabled);
+    });
   },
 };
diff --git a/app/assets/javascripts/discourse/app/initializers/welcome-topic-banner.js b/app/assets/javascripts/discourse/app/initializers/welcome-topic-banner.js
index b00f24f83dc..e161df53d38 100644
--- a/app/assets/javascripts/discourse/app/initializers/welcome-topic-banner.js
+++ b/app/assets/javascripts/discourse/app/initializers/welcome-topic-banner.js
@@ -1,24 +1,15 @@
-import { bind } from "discourse-common/utils/decorators";
-
 export default {
   name: "welcome-topic-banner",
   after: "message-bus",
 
   initialize(container) {
-    this.site = container.lookup("service:site");
-    this.messageBus = container.lookup("service:message-bus");
+    const site = container.lookup("service:site");
 
-    if (this.site.show_welcome_topic_banner) {
-      this.messageBus.subscribe("/site/welcome-topic-banner", this.onMessage);
+    if (site.show_welcome_topic_banner) {
+      const messageBus = container.lookup("service:message-bus");
+      messageBus.subscribe("/site/welcome-topic-banner", (disabled) => {
+        site.set("show_welcome_topic_banner", disabled);
+      });
     }
   },
-
-  teardown() {
-    this.messageBus.unsubscribe("/site/welcome-topic-banner", this.onMessage);
-  },
-
-  @bind
-  onMessage(disabled) {
-    this.site.set("show_welcome_topic_banner", disabled);
-  },
 };
diff --git a/app/assets/javascripts/discourse/app/models/topic-tracking-state.js b/app/assets/javascripts/discourse/app/models/topic-tracking-state.js
index 50d05a2fde7..4fa65a43b59 100644
--- a/app/assets/javascripts/discourse/app/models/topic-tracking-state.js
+++ b/app/assets/javascripts/discourse/app/models/topic-tracking-state.js
@@ -1,5 +1,5 @@
 import EmberObject, { get } from "@ember/object";
-import discourseComputed, { bind } from "discourse-common/utils/decorators";
+import discourseComputed, { bind, on } from "discourse-common/utils/decorators";
 import Category from "discourse/models/category";
 import { deepEqual, deepMerge } from "discourse-common/lib/object";
 import DiscourseURL from "discourse/lib/url";
@@ -46,33 +46,13 @@ function hasMutedTags(topicTags, mutedTags, siteSettings) {
 const TopicTrackingState = EmberObject.extend({
   messageCount: 0,
 
-  init() {
-    this._super(...arguments);
-
+  @on("init")
+  _setup() {
     this.states = new Map();
     this.stateChangeCallbacks = {};
     this._trackedTopicLimit = 4000;
   },
 
-  willDestroy() {
-    this._super(...arguments);
-
-    this.messageBus.unsubscribe("/latest", this._processChannelPayload);
-
-    if (this.currentUser) {
-      this.messageBus.unsubscribe("/new", this._processChannelPayload);
-      this.messageBus.unsubscribe(`/unread`, this._processChannelPayload);
-      this.messageBus.unsubscribe(
-        `/unread/${this.currentUser.id}`,
-        this._processChannelPayload
-      );
-    }
-
-    this.messageBus.unsubscribe("/delete", this.onDeleteMessage);
-    this.messageBus.unsubscribe("/recover", this.onRecoverMessage);
-    this.messageBus.unsubscribe("/destroy", this.onDestroyMessage);
-  },
-
   /**
    * Subscribe to MessageBus channels which are used for publishing changes
    * to the tracking state. Each message received will modify state for
@@ -94,34 +74,26 @@ const TopicTrackingState = EmberObject.extend({
       );
     }
 
-    this.messageBus.subscribe("/delete", this.onDeleteMessage);
-    this.messageBus.subscribe("/recover", this.onRecoverMessage);
-    this.messageBus.subscribe("/destroy", this.onDestroyMessage);
-  },
+    this.messageBus.subscribe("/delete", (msg) => {
+      this.modifyStateProp(msg, "deleted", true);
+      this.incrementMessageCount();
+    });
 
-  @bind
-  onDeleteMessage(msg) {
-    this.modifyStateProp(msg, "deleted", true);
-    this.incrementMessageCount();
-  },
+    this.messageBus.subscribe("/recover", (msg) => {
+      this.modifyStateProp(msg, "deleted", false);
+      this.incrementMessageCount();
+    });
 
-  @bind
-  onRecoverMessage(msg) {
-    this.modifyStateProp(msg, "deleted", false);
-    this.incrementMessageCount();
-  },
-
-  @bind
-  onDestroyMessage(msg) {
-    this.incrementMessageCount();
-    const currentRoute = DiscourseURL.router.currentRoute.parent;
-
-    if (
-      currentRoute.name === "topic" &&
-      parseInt(currentRoute.params.id, 10) === msg.topic_id
-    ) {
-      DiscourseURL.redirectTo("/");
-    }
+    this.messageBus.subscribe("/destroy", (msg) => {
+      this.incrementMessageCount();
+      const currentRoute = DiscourseURL.router.currentRoute.parent;
+      if (
+        currentRoute.name === "topic" &&
+        parseInt(currentRoute.params.id, 10) === msg.topic_id
+      ) {
+        DiscourseURL.redirectTo("/");
+      }
+    });
   },
 
   mutedTopics() {
@@ -308,7 +280,7 @@ const TopicTrackingState = EmberObject.extend({
    * @param {String} filter - Valid values are all, categories, and any topic list
    *                          filters e.g. latest, unread, new. As well as this
    *                          specific category and tag URLs like tag/test/l/latest,
-   *                          c/cat/sub-cat/6/l/latest or tags/c/cat/sub-cat/6/test/l/latest.
+   *                          c/cat/subcat/6/l/latest or tags/c/cat/subcat/6/test/l/latest.
    */
   trackIncoming(filter) {
     this.newIncoming = [];
@@ -340,7 +312,7 @@ const TopicTrackingState = EmberObject.extend({
   },
 
   /**
-   * Used to determine whether to show the message at the top of the topic list
+   * Used to determine whether toshow the message at the top of the topic list
    * e.g. "see 1 new or updated topic"
    *
    * @method incomingCount
@@ -583,7 +555,7 @@ const TopicTrackingState = EmberObject.extend({
   },
 
   /**
-   * Using the array of tags provided, tallies up all topics via forEachTracked
+   * Using the array of tags provided, tallys up all topics via forEachTracked
    * that we are tracking, separated into new/unread/total.
    *
    * Total is only counted if opts.includeTotal is specified.
diff --git a/app/assets/javascripts/discourse/app/pre-initializers/inject-discourse-objects.js b/app/assets/javascripts/discourse/app/pre-initializers/inject-discourse-objects.js
index b8b50155932..ba54502f20c 100644
--- a/app/assets/javascripts/discourse/app/pre-initializers/inject-discourse-objects.js
+++ b/app/assets/javascripts/discourse/app/pre-initializers/inject-discourse-objects.js
@@ -40,13 +40,13 @@ export default {
     // to register a null value for anon
     app.register("service:current-user", currentUser, { instantiate: false });
 
-    this.topicTrackingState = TopicTrackingState.create({
+    const topicTrackingState = TopicTrackingState.create({
       messageBus: container.lookup("service:message-bus"),
       siteSettings,
       currentUser,
     });
 
-    app.register("service:topic-tracking-state", this.topicTrackingState, {
+    app.register("service:topic-tracking-state", topicTrackingState, {
       instantiate: false,
     });
 
@@ -108,11 +108,6 @@ export default {
       });
     }
 
-    startTracking(this.topicTrackingState);
-  },
-
-  teardown() {
-    // Manually call `willDestroy` as this isn't an actual `Service`
-    this.topicTrackingState.willDestroy();
+    startTracking(topicTrackingState);
   },
 };
diff --git a/app/assets/javascripts/discourse/app/routes/review-index.js b/app/assets/javascripts/discourse/app/routes/review-index.js
index 23fd3ab4450..074b2079948 100644
--- a/app/assets/javascripts/discourse/app/routes/review-index.js
+++ b/app/assets/javascripts/discourse/app/routes/review-index.js
@@ -1,7 +1,6 @@
 import DiscourseRoute from "discourse/routes/discourse";
 import { isPresent } from "@ember/utils";
 import { action } from "@ember/object";
-import { bind } from "discourse-common/utils/decorators";
 
 export default DiscourseRoute.extend({
   model(params) {
@@ -52,9 +51,34 @@ export default DiscourseRoute.extend({
   },
 
   activate() {
+    this._updateClaimedBy = (data) => {
+      const reviewables = this.controller.reviewables;
+      if (reviewables) {
+        const user = data.user
+          ? this.store.createRecord("user", data.user)
+          : null;
+        reviewables.forEach((reviewable) => {
+          if (data.topic_id === reviewable.topic.id) {
+            reviewable.set("claimed_by", user);
+          }
+        });
+      }
+    };
+
+    this._updateReviewables = (data) => {
+      if (data.updates) {
+        this.controller.reviewables.forEach((reviewable) => {
+          const updates = data.updates[reviewable.id];
+          if (updates) {
+            reviewable.setProperties(updates);
+          }
+        });
+      }
+    };
+
     this.messageBus.subscribe("/reviewable_claimed", this._updateClaimedBy);
     this.messageBus.subscribe(
-      this._reviewableCountsChannel,
+      this._reviewableCountsChannel(),
       this._updateReviewables
     );
   },
@@ -62,46 +86,19 @@ export default DiscourseRoute.extend({
   deactivate() {
     this.messageBus.unsubscribe("/reviewable_claimed", this._updateClaimedBy);
     this.messageBus.unsubscribe(
-      this._reviewableCountsChannel,
+      this._reviewableCountsChannel(),
       this._updateReviewables
     );
   },
 
-  @bind
-  _updateClaimedBy(data) {
-    const reviewables = this.controller.reviewables;
-    if (reviewables) {
-      const user = data.user
-        ? this.store.createRecord("user", data.user)
-        : null;
-      reviewables.forEach((reviewable) => {
-        if (data.topic_id === reviewable.topic.id) {
-          reviewable.set("claimed_by", user);
-        }
-      });
-    }
-  },
-
-  @bind
-  _updateReviewables(data) {
-    if (data.updates) {
-      this.controller.reviewables.forEach((reviewable) => {
-        const updates = data.updates[reviewable.id];
-        if (updates) {
-          reviewable.setProperties(updates);
-        }
-      });
-    }
-  },
-
-  get _reviewableCountsChannel() {
-    return this.currentUser.redesigned_user_menu_enabled
-      ? `/reviewable_counts/${this.currentUser.id}`
-      : "/reviewable_counts";
-  },
-
   @action
   refreshRoute() {
     this.refresh();
   },
+
+  _reviewableCountsChannel() {
+    return this.currentUser.redesigned_user_menu_enabled
+      ? `/reviewable_counts/${this.currentUser.id}`
+      : "/reviewable_counts";
+  },
 });
diff --git a/app/assets/javascripts/discourse/app/routes/user.js b/app/assets/javascripts/discourse/app/routes/user.js
index b3efdef6878..c33c8d1b6cc 100644
--- a/app/assets/javascripts/discourse/app/routes/user.js
+++ b/app/assets/javascripts/discourse/app/routes/user.js
@@ -2,9 +2,25 @@ import DiscourseRoute from "discourse/routes/discourse";
 import I18n from "I18n";
 import User from "discourse/models/user";
 import { action } from "@ember/object";
-import { bind } from "discourse-common/utils/decorators";
 
 export default DiscourseRoute.extend({
+  titleToken() {
+    const username = this.modelFor("user").username;
+    if (username) {
+      return [I18n.t("user.profile"), username];
+    }
+  },
+
+  @action
+  undoRevokeApiKey(key) {
+    key.undoRevoke();
+  },
+
+  @action
+  revokeApiKey(key) {
+    key.revoke();
+  },
+
   beforeModel() {
     if (this.siteSettings.hide_user_profiles_from_public && !this.currentUser) {
       this.replaceWith("discovery");
@@ -52,64 +68,29 @@ export default DiscourseRoute.extend({
     this._super(...arguments);
 
     const user = this.modelFor("user");
-    this.messageBus.subscribe(`/u/${user.username_lower}`, this.onUserMessage);
-    this.messageBus.subscribe(
-      `/u/${user.username_lower}/counters`,
-      this.onUserCountersMessage
+    this.messageBus.subscribe(`/u/${user.username_lower}`, (data) =>
+      user.loadUserAction(data)
     );
+    this.messageBus.subscribe(`/u/${user.username_lower}/counters`, (data) => {
+      user.setProperties(data);
+      Object.entries(data).forEach(([key, value]) =>
+        this.appEvents.trigger(
+          `count-updated:${user.username_lower}:${key}`,
+          value
+        )
+      );
+    });
   },
 
   deactivate() {
     this._super(...arguments);
 
     const user = this.modelFor("user");
-    this.messageBus.unsubscribe(
-      `/u/${user.username_lower}`,
-      this.onUserMessage
-    );
-    this.messageBus.unsubscribe(
-      `/u/${user.username_lower}/counters`,
-      this.onUserCountersMessage
-    );
+    this.messageBus.unsubscribe(`/u/${user.username_lower}`);
+    this.messageBus.unsubscribe(`/u/${user.username_lower}/counters`);
     user.stopTrackingStatus();
 
     // Remove the search context
     this.searchService.set("searchContext", null);
   },
-
-  @bind
-  onUserMessage(data) {
-    const user = this.modelFor("user");
-    return user.loadUserAction(data);
-  },
-
-  @bind
-  onUserCountersMessage(data) {
-    const user = this.modelFor("user");
-    user.setProperties(data);
-
-    Object.entries(data).forEach(([key, value]) =>
-      this.appEvents.trigger(
-        `count-updated:${user.username_lower}:${key}`,
-        value
-      )
-    );
-  },
-
-  titleToken() {
-    const username = this.modelFor("user").username;
-    if (username) {
-      return [I18n.t("user.profile"), username];
-    }
-  },
-
-  @action
-  undoRevokeApiKey(key) {
-    key.undoRevoke();
-  },
-
-  @action
-  revokeApiKey(key) {
-    key.revoke();
-  },
 });
diff --git a/app/assets/javascripts/discourse/app/services/logs-notice.js b/app/assets/javascripts/discourse/app/services/logs-notice.js
index 2b3276ae76e..2e3143a9076 100644
--- a/app/assets/javascripts/discourse/app/services/logs-notice.js
+++ b/app/assets/javascripts/discourse/app/services/logs-notice.js
@@ -1,7 +1,4 @@
-import discourseComputed, {
-  bind,
-  observes,
-} from "discourse-common/utils/decorators";
+import discourseComputed, { observes } from "discourse-common/utils/decorators";
 import Service from "@ember/service";
 import I18n from "I18n";
 import { autoUpdatingRelativeAge } from "discourse/lib/formatter";
@@ -32,41 +29,32 @@ export default Service.extend({
       this.set("text", text);
     }
 
-    this.messageBus.subscribe("/logs_error_rate_exceeded", this.onLogRateLimit);
-  },
+    this.messageBus.subscribe("/logs_error_rate_exceeded", (data) => {
+      const duration = data.duration;
+      const rate = data.rate;
+      let siteSettingLimit = 0;
 
-  willDestroy() {
-    this._super(...arguments);
+      if (duration === "minute") {
+        siteSettingLimit = this.siteSettings.alert_admins_if_errors_per_minute;
+      } else if (duration === "hour") {
+        siteSettingLimit = this.siteSettings.alert_admins_if_errors_per_hour;
+      }
 
-    this.messageBus.unsubscribe(
-      "/logs_error_rate_exceeded",
-      this.onLogRateLimit
-    );
-  },
+      let translationKey = rate === siteSettingLimit ? "reached" : "exceeded";
+      translationKey += `_${duration}_MF`;
 
-  @bind
-  onLogRateLimit(data) {
-    const { duration, rate } = data;
-    let siteSettingLimit = 0;
-
-    if (duration === "minute") {
-      siteSettingLimit = this.siteSettings.alert_admins_if_errors_per_minute;
-    } else if (duration === "hour") {
-      siteSettingLimit = this.siteSettings.alert_admins_if_errors_per_hour;
-    }
-
-    let translationKey = rate === siteSettingLimit ? "reached" : "exceeded";
-    translationKey += `_${duration}_MF`;
-
-    this.set(
-      "text",
-      I18n.messageFormat(`logs_error_rate_notice.${translationKey}`, {
-        relativeAge: autoUpdatingRelativeAge(new Date(data.publish_at * 1000)),
-        rate,
-        limit: siteSettingLimit,
-        url: getURL("/logs"),
-      })
-    );
+      this.set(
+        "text",
+        I18n.messageFormat(`logs_error_rate_notice.${translationKey}`, {
+          relativeAge: autoUpdatingRelativeAge(
+            new Date(data.publish_at * 1000)
+          ),
+          rate,
+          limit: siteSettingLimit,
+          url: getURL("/logs"),
+        })
+      );
+    });
   },
 
   @discourseComputed("text")
diff --git a/app/assets/javascripts/discourse/app/services/pm-topic-tracking-state.js b/app/assets/javascripts/discourse/app/services/pm-topic-tracking-state.js
index 4c841b9fbe8..1afefabbff1 100644
--- a/app/assets/javascripts/discourse/app/services/pm-topic-tracking-state.js
+++ b/app/assets/javascripts/discourse/app/services/pm-topic-tracking-state.js
@@ -1,7 +1,8 @@
 import { Promise } from "rsvp";
+
 import Service from "@ember/service";
 import { ajax } from "discourse/lib/ajax";
-import { bind } from "discourse-common/utils/decorators";
+import { bind, on } from "discourse-common/utils/decorators";
 import { popupAjaxError } from "discourse/lib/ajax-error";
 import { deepEqual, deepMerge } from "discourse-common/lib/object";
 import {
@@ -20,9 +21,8 @@ const PrivateMessageTopicTrackingState = Service.extend({
   filter: null,
   activeGroup: null,
 
-  init() {
-    this._super(...arguments);
-
+  @on("init")
+  _setup() {
     this.states = new Map();
     this.statesModificationCounter = 0;
     this.isTracking = false;
@@ -30,16 +30,6 @@ const PrivateMessageTopicTrackingState = Service.extend({
     this.stateChangeCallbacks = new Map();
   },
 
-  willDestroy() {
-    this._super(...arguments);
-
-    if (this.currentUser) {
-      this.messageBus.unsubscribe(this.userChannel(), this._processMessage);
-    }
-
-    this.messageBus.unsubscribe(this.groupChannel("*"), this._processMessage);
-  },
-
   onStateChange(key, callback) {
     this.stateChangeCallbacks.set(key, callback);
   },
@@ -53,6 +43,14 @@ const PrivateMessageTopicTrackingState = Service.extend({
       return Promise.resolve();
     }
 
+    this._establishChannels();
+
+    return this._loadInitialState().finally(() => {
+      this.set("isTracking", true);
+    });
+  },
+
+  _establishChannels() {
     this.messageBus.subscribe(this.userChannel(), this._processMessage);
 
     this.currentUser.groupsWithMessages?.forEach((group) => {
@@ -61,10 +59,6 @@ const PrivateMessageTopicTrackingState = Service.extend({
         this._processMessage
       );
     });
-
-    return this._loadInitialState().finally(() => {
-      this.set("isTracking", true);
-    });
   },
 
   lookupCount(type, opts = {}) {
diff --git a/plugins/discourse-narrative-bot/assets/javascripts/initializers/new-user-narrative.js b/plugins/discourse-narrative-bot/assets/javascripts/initializers/new-user-narrative.js
index d34421cf670..4b12e22bad2 100644
--- a/plugins/discourse-narrative-bot/assets/javascripts/initializers/new-user-narrative.js
+++ b/plugins/discourse-narrative-bot/assets/javascripts/initializers/new-user-narrative.js
@@ -1,4 +1,4 @@
-import { bind, debounce } from "discourse-common/utils/decorators";
+import { debounce } from "discourse-common/utils/decorators";
 import { ajax } from "discourse/lib/ajax";
 import { headerOffset } from "discourse/lib/offset-calculator";
 import isElementInViewport from "discourse/lib/is-element-in-viewport";
@@ -43,32 +43,35 @@ function initialize(api) {
       return this._super(bookmark, post);
     },
 
-    @bind
-    onMessage(data) {
+    subscribe() {
       this._super(...arguments);
 
-      const topic = this.model;
-
-      // scroll only for discobot (-2 is discobot id)
-      if (
-        topic.isPrivateMessage &&
-        this.currentUser &&
-        this.currentUser.id !== data.user_id &&
-        data.user_id === -2 &&
-        data.type === "created"
-      ) {
-        const postNumber = data.post_number;
-        const notInPostStream = topic.get("highest_post_number") <= postNumber;
-        const postNumberDifference = postNumber - topic.currentPost;
+      this.messageBus.subscribe(`/topic/${this.model.id}`, (data) => {
+        const topic = this.model;
 
+        // scroll only for discobot (-2 is discobot id)
         if (
-          notInPostStream &&
-          postNumberDifference > 0 &&
-          postNumberDifference < 7
+          topic.isPrivateMessage &&
+          this.currentUser &&
+          this.currentUser.id !== data.user_id &&
+          data.user_id === -2 &&
+          data.type === "created"
         ) {
-          this._scrollToDiscobotPost(data.post_number);
+          const postNumber = data.post_number;
+          const notInPostStream =
+            topic.get("highest_post_number") <= postNumber;
+          const postNumberDifference = postNumber - topic.currentPost;
+
+          if (
+            notInPostStream &&
+            postNumberDifference > 0 &&
+            postNumberDifference < 7
+          ) {
+            this._scrollToDiscobotPost(data.post_number);
+          }
         }
-      }
+      });
+      // No need to unsubscribe, core unsubscribes /topic/* routes
     },
 
     @debounce(500)
diff --git a/plugins/poll/assets/javascripts/initializers/extend-for-poll.js b/plugins/poll/assets/javascripts/initializers/extend-for-poll.js
index a22b322130e..cd04356b1a0 100644
--- a/plugins/poll/assets/javascripts/initializers/extend-for-poll.js
+++ b/plugins/poll/assets/javascripts/initializers/extend-for-poll.js
@@ -1,7 +1,7 @@
 import EmberObject from "@ember/object";
 import WidgetGlue from "discourse/widgets/glue";
 import { getRegister } from "discourse-common/lib/get-owner";
-import { bind, observes } from "discourse-common/utils/decorators";
+import { observes } from "discourse-common/utils/decorators";
 import { withPluginApi } from "discourse/lib/plugin-api";
 
 const PLUGIN_ID = "discourse-poll";
@@ -34,19 +34,16 @@ function initializePolls(api) {
 
     subscribe() {
       this._super(...arguments);
-      this.messageBus.subscribe(`/polls/${this.model.id}`, this._onPollMessage);
+      this.messageBus.subscribe(`/polls/${this.model.id}`, (msg) => {
+        const post = this.get("model.postStream").findLoadedPost(msg.post_id);
+        post?.set("polls", msg.polls);
+      });
     },
 
     unsubscribe() {
-      this.messageBus.unsubscribe("/polls/*", this._onPollMessage);
+      this.messageBus.unsubscribe("/polls/*");
       this._super(...arguments);
     },
-
-    @bind
-    _onPollMessage(msg) {
-      const post = this.get("model.postStream").findLoadedPost(msg.post_id);
-      post?.set("polls", msg.polls);
-    },
   });
 
   api.modifyClass("model:post", {