From e17274b15c29e2f392d11e012c04553f6d4e4765 Mon Sep 17 00:00:00 2001
From: NullVoxPopuli <199018+NullVoxPopuli@users.noreply.github.com>
Date: Mon, 19 May 2025 10:34:44 -0400
Subject: [PATCH 1/3] Remove unneeded restriction around creating
 sub-applications

---
 .../views/lib/system/event_dispatcher.ts          | 15 ---------------
 1 file changed, 15 deletions(-)

diff --git a/packages/@ember/-internals/views/lib/system/event_dispatcher.ts b/packages/@ember/-internals/views/lib/system/event_dispatcher.ts
index db3512393fc..30082d5c385 100644
--- a/packages/@ember/-internals/views/lib/system/event_dispatcher.ts
+++ b/packages/@ember/-internals/views/lib/system/event_dispatcher.ts
@@ -162,21 +162,6 @@ export default class EventDispatcher extends EmberObject {
       `You cannot use the same root element (${specifiedRootElement}) multiple times in an Ember.Application`,
       !rootElement.classList.contains(ROOT_ELEMENT_CLASS)
     );
-    assert(
-      'You cannot make a new Ember.Application using a root element that is a descendent of an existing Ember.Application',
-      (() => {
-        let target = rootElement.parentNode;
-        while (target instanceof Element) {
-          if (target.classList.contains(ROOT_ELEMENT_CLASS)) {
-            return false;
-          }
-
-          target = target.parentNode;
-        }
-
-        return true;
-      })()
-    );
     assert(
       'You cannot make a new Ember.Application using a root element that is an ancestor of an existing Ember.Application',
       !rootElement.querySelector(ROOT_ELEMENT_SELECTOR)

From 420d454a94b088ba17f5c209af30dfee77066227 Mon Sep 17 00:00:00 2001
From: NullVoxPopuli <199018+NullVoxPopuli@users.noreply.github.com>
Date: Mon, 19 May 2025 10:45:14 -0400
Subject: [PATCH 2/3] Remove test that is no longer relevant

---
 packages/@ember/application/tests/application_test.js | 10 ----------
 1 file changed, 10 deletions(-)

diff --git a/packages/@ember/application/tests/application_test.js b/packages/@ember/application/tests/application_test.js
index 71fdd5c2fa7..e6336b685fc 100644
--- a/packages/@ember/application/tests/application_test.js
+++ b/packages/@ember/application/tests/application_test.js
@@ -74,16 +74,6 @@ moduleFor(
       });
     }
 
-    [`@test you cannot make a new application that is a descendant of an existing application`]() {
-      expectAssertion(() => {
-        runTask(() =>
-          this.createSecondApplication({
-            rootElement: '#one-child',
-          })
-        );
-      });
-    }
-
     [`@test you cannot make a new application that is a duplicate of an existing application`]() {
       expectAssertion(() => {
         runTask(() =>

From 16e9ebbea7c1d2934e626e60fd24674c5e9b02bb Mon Sep 17 00:00:00 2001
From: NullVoxPopuli <199018+NullVoxPopuli@users.noreply.github.com>
Date: Tue, 22 Jul 2025 10:31:44 -0400
Subject: [PATCH 3/3] Remove another assert

---
 .../@ember/-internals/views/lib/system/event_dispatcher.ts  | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/packages/@ember/-internals/views/lib/system/event_dispatcher.ts b/packages/@ember/-internals/views/lib/system/event_dispatcher.ts
index 30082d5c385..091792fab6f 100644
--- a/packages/@ember/-internals/views/lib/system/event_dispatcher.ts
+++ b/packages/@ember/-internals/views/lib/system/event_dispatcher.ts
@@ -13,7 +13,6 @@ import type { ActionState } from '@ember/-internals/glimmer/lib/modifiers/action
 */
 
 const ROOT_ELEMENT_CLASS = 'ember-application';
-const ROOT_ELEMENT_SELECTOR = `.${ROOT_ELEMENT_CLASS}`;
 
 /**
   `Ember.EventDispatcher` handles delegating browser events to their
@@ -162,11 +161,6 @@ export default class EventDispatcher extends EmberObject {
       `You cannot use the same root element (${specifiedRootElement}) multiple times in an Ember.Application`,
       !rootElement.classList.contains(ROOT_ELEMENT_CLASS)
     );
-    assert(
-      'You cannot make a new Ember.Application using a root element that is an ancestor of an existing Ember.Application',
-      !rootElement.querySelector(ROOT_ELEMENT_SELECTOR)
-    );
-
     rootElement.classList.add(ROOT_ELEMENT_CLASS);
 
     assert(