diff --git a/app/assets/javascripts/discourse/tests/integration/components/d-button-test.js b/app/assets/javascripts/discourse/tests/integration/components/d-button-test.js
index d614209b61d..ac0068ff867 100644
--- a/app/assets/javascripts/discourse/tests/integration/components/d-button-test.js
+++ b/app/assets/javascripts/discourse/tests/integration/components/d-button-test.js
@@ -250,6 +250,7 @@ module("Integration | Component | d-button", function (hooks) {
     this.set("foo", null);
     this.set("legacyActionTriggered", () => this.set("foo", "bar"));
 
+    // eslint-disable-next-line ember/no-classic-classes
     this.classicComponent = ClassicComponent.extend({
       actions: {
         myLegacyAction() {
@@ -277,8 +278,9 @@ module("Integration | Component | d-button", function (hooks) {
     this.set("foo", null);
     this.set("legacyActionTriggered", () => this.set("foo", "bar"));
 
-    this.simpleWrapperComponent = ClassicComponent.extend();
+    this.simpleWrapperComponent = class extends ClassicComponent {};
 
+    // eslint-disable-next-line ember/no-classic-classes
     this.classicComponent = ClassicComponent.extend({
       actions: {
         myLegacyAction() {
diff --git a/app/assets/javascripts/discourse/tests/unit/lib/ember-action-modifer-test.js b/app/assets/javascripts/discourse/tests/unit/lib/ember-action-modifer-test.js
index 824604aaca9..31baee23ef5 100644
--- a/app/assets/javascripts/discourse/tests/unit/lib/ember-action-modifer-test.js
+++ b/app/assets/javascripts/discourse/tests/unit/lib/ember-action-modifer-test.js
@@ -76,15 +76,16 @@ module("Unit | Lib | ember-action-modifier", function (hooks) {
   });
 
   module("used on a classic component", function (innerHooks) {
-    const ExampleClassicButton = ClassicComponent.extend({
-      tagName: "",
-      onDoSomething: null,
+    class ExampleClassicButton extends ClassicComponent {
+      tagName = "";
+      onDoSomething = null;
 
       doSomething() {
         this.onDoSomething?.("doSomething");
-      },
-    });
+      }
+    }
 
+    // eslint-disable-next-line ember/no-classic-classes
     const ExampleClassicButtonWithActions = ClassicComponent.extend({
       tagName: "",
       onDoSomething: null,
diff --git a/app/assets/javascripts/discourse/tests/unit/lib/plugin-api-test.js b/app/assets/javascripts/discourse/tests/unit/lib/plugin-api-test.js
index f1763ac0e24..7b708d2e321 100644
--- a/app/assets/javascripts/discourse/tests/unit/lib/plugin-api-test.js
+++ b/app/assets/javascripts/discourse/tests/unit/lib/plugin-api-test.js
@@ -1,4 +1,4 @@
-import EmberObject from "@ember/object";
+import EmberObject, { computed } from "@ember/object";
 import { getOwner } from "@ember/owner";
 import { setupTest } from "ember-qunit";
 import { module, test } from "qunit";
@@ -10,11 +10,11 @@ module("Unit | Utility | plugin-api", function (hooks) {
   setupTest(hooks);
 
   test("modifyClass works with classic Ember objects", function (assert) {
+    // eslint-disable-next-line ember/no-classic-classes
     const TestThingy = EmberObject.extend({
-      @discourseComputed
-      prop() {
+      prop: computed(function () {
         return "hello";
-      },
+      }),
     });
 
     getOwner(this).register("test-thingy:main", TestThingy);
@@ -23,10 +23,9 @@ module("Unit | Utility | plugin-api", function (hooks) {
       api.modifyClass("test-thingy:main", {
         pluginId: "plugin-api-test",
 
-        @discourseComputed
-        prop() {
+        prop: computed(function () {
           return `${this._super(...arguments)} there`;
-        },
+        }),
       });
     });
 
@@ -90,11 +89,11 @@ module("Unit | Utility | plugin-api", function (hooks) {
   });
 
   test("modifyClass works with getters", function (assert) {
-    let Base = EmberObject.extend({
+    let Base = class extends EmberObject {
       get foo() {
         throw new Error("base getter called");
-      },
-    });
+      }
+    };
 
     getOwner(this).register("test-class:main", Base, {
       instantiate: false,
diff --git a/app/assets/javascripts/discourse/tests/unit/mixins/singleton-test.js b/app/assets/javascripts/discourse/tests/unit/mixins/singleton-test.js
index b1ea6606df7..b3a805685f8 100644
--- a/app/assets/javascripts/discourse/tests/unit/mixins/singleton-test.js
+++ b/app/assets/javascripts/discourse/tests/unit/mixins/singleton-test.js
@@ -7,7 +7,7 @@ module("Unit | Mixin | singleton", function (hooks) {
   setupTest(hooks);
 
   test("current", function (assert) {
-    let DummyModel = EmberObject.extend({});
+    let DummyModel = class extends EmberObject {};
     DummyModel.reopenClass(Singleton);
 
     let current = DummyModel.current();
@@ -25,7 +25,7 @@ module("Unit | Mixin | singleton", function (hooks) {
   });
 
   test("currentProp reading", function (assert) {
-    let DummyModel = EmberObject.extend({});
+    let DummyModel = class extends EmberObject {};
     DummyModel.reopenClass(Singleton);
     let current = DummyModel.current();
 
@@ -42,7 +42,7 @@ module("Unit | Mixin | singleton", function (hooks) {
   });
 
   test("currentProp writing", function (assert) {
-    let DummyModel = EmberObject.extend({});
+    let DummyModel = class extends EmberObject {};
     DummyModel.reopenClass(Singleton);
 
     assert.blank(
@@ -73,7 +73,7 @@ module("Unit | Mixin | singleton", function (hooks) {
   });
 
   test("createCurrent", function (assert) {
-    let Shoe = EmberObject.extend({});
+    let Shoe = class extends EmberObject {};
     Shoe.reopenClass(Singleton, {
       createCurrent: function () {
         return Shoe.create({ toes: 5 });
@@ -88,7 +88,7 @@ module("Unit | Mixin | singleton", function (hooks) {
   });
 
   test("createCurrent that returns null", function (assert) {
-    let Missing = EmberObject.extend({});
+    let Missing = class extends EmberObject {};
     Missing.reopenClass(Singleton, {
       createCurrent: function () {
         return null;
diff --git a/app/assets/javascripts/discourse/tests/unit/utils/decorators-test.js b/app/assets/javascripts/discourse/tests/unit/utils/decorators-test.js
index eb8628ae01e..8d9d6c19565 100644
--- a/app/assets/javascripts/discourse/tests/unit/utils/decorators-test.js
+++ b/app/assets/javascripts/discourse/tests/unit/utils/decorators-test.js
@@ -1,3 +1,5 @@
+// eslint-disable ember/no-classic-classes
+
 import Component from "@ember/component";
 import EmberObject from "@ember/object";
 import { clearRender, render, settled } from "@ember/test-helpers";
diff --git a/app/assets/javascripts/discourse/tests/unit/utils/optional-service-test.js b/app/assets/javascripts/discourse/tests/unit/utils/optional-service-test.js
index 4008c9e3ff2..981a214df14 100644
--- a/app/assets/javascripts/discourse/tests/unit/utils/optional-service-test.js
+++ b/app/assets/javascripts/discourse/tests/unit/utils/optional-service-test.js
@@ -14,6 +14,7 @@ class BarService extends Service {
   name = "bar";
 }
 
+// eslint-disable-next-line ember/no-classic-classes
 const EmberObjectComponent = Component.extend({
   name: "",
   layout: hbs`<span class="ember-object-component">{{this.foo.name}} {{this.baz.name}}</span>`,