From b5215013bde00482db16b1c76350e1be1d99dc3c Mon Sep 17 00:00:00 2001
From: NullVoxPopuli <199018+NullVoxPopuli@users.noreply.github.com>
Date: Tue, 3 Mar 2026 15:27:13 -0500
Subject: [PATCH 1/2] Fix #20984: crash *during* destroy in fastboot

---
 packages/@ember/-internals/glimmer/lib/renderer.ts | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/packages/@ember/-internals/glimmer/lib/renderer.ts b/packages/@ember/-internals/glimmer/lib/renderer.ts
index 2a0847d4818..96824559dea 100644
--- a/packages/@ember/-internals/glimmer/lib/renderer.ts
+++ b/packages/@ember/-internals/glimmer/lib/renderer.ts
@@ -232,7 +232,16 @@ class ClassicRootState {
 
       let result = (this.result = iterator.sync());
 
-      associateDestroyableChild(owner, result);
+      // Associate the result with the root state (not the owner) so that
+      // destruction cascades through:
+      //   Owner → Container → Renderer → RendererState → ClassicRootState → result
+      // This ensures the container is still alive when component destructors
+      // run (e.g. willDestroy looking up the renderer via injection).
+      // Previously, associating with the owner made the result a sibling of
+      // the Container, causing the Container to be destroyed first — which
+      // broke FastBoot where the container was already dead by the time
+      // component teardown tried to do lookups. (See: emberjs/ember.js#20984)
+      associateDestroyableChild(this, result);
 
       this.render = errorLoopTransaction(() => {
         if (isDestroying(result) || isDestroyed(result)) return;

From 00e7e184bf3e67ba800ef3598fc4630a48cb0aaf Mon Sep 17 00:00:00 2001
From: NullVoxPopuli <199018+NullVoxPopuli@users.noreply.github.com>
Date: Tue, 3 Mar 2026 15:52:50 -0500
Subject: [PATCH 2/2] Clean up comments in renderer.ts

Remove outdated comments regarding result association with root state.
---
 packages/@ember/-internals/glimmer/lib/renderer.ts | 9 ---------
 1 file changed, 9 deletions(-)

diff --git a/packages/@ember/-internals/glimmer/lib/renderer.ts b/packages/@ember/-internals/glimmer/lib/renderer.ts
index 96824559dea..0bcd9cd7b19 100644
--- a/packages/@ember/-internals/glimmer/lib/renderer.ts
+++ b/packages/@ember/-internals/glimmer/lib/renderer.ts
@@ -232,15 +232,6 @@ class ClassicRootState {
 
       let result = (this.result = iterator.sync());
 
-      // Associate the result with the root state (not the owner) so that
-      // destruction cascades through:
-      //   Owner → Container → Renderer → RendererState → ClassicRootState → result
-      // This ensures the container is still alive when component destructors
-      // run (e.g. willDestroy looking up the renderer via injection).
-      // Previously, associating with the owner made the result a sibling of
-      // the Container, causing the Container to be destroyed first — which
-      // broke FastBoot where the container was already dead by the time
-      // component teardown tried to do lookups. (See: emberjs/ember.js#20984)
       associateDestroyableChild(this, result);
 
       this.render = errorLoopTransaction(() => {