From 5e4df55bced8676dbb088bba209fada0d13ff284 Mon Sep 17 00:00:00 2001
From: linzhe141 <1572213544@qq.com>
Date: Wed, 12 Nov 2025 15:16:23 +0800
Subject: [PATCH 1/3] fix(suspense): defer clearing fallback vnode reference to
 should unmount active branch first

---
 .../runtime-core/src/components/Suspense.ts     | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/packages/runtime-core/src/components/Suspense.ts b/packages/runtime-core/src/components/Suspense.ts
index d14e96be3d0..4731e939409 100644
--- a/packages/runtime-core/src/components/Suspense.ts
+++ b/packages/runtime-core/src/components/Suspense.ts
@@ -20,6 +20,7 @@ import {
   type RendererInternals,
   type RendererNode,
   type SetupRenderEffectFn,
+  queuePostRenderEffect,
 } from '../renderer'
 import { queuePostFlushCb } from '../scheduler'
 import { filterSingleRoot, updateHOCHostEl } from '../componentRenderUtils'
@@ -553,9 +554,11 @@ function createSuspenseBoundary(
               )
               queuePostFlushCb(effects)
               // clear el reference from fallback vnode to allow GC after transition
-              if (isInFallback && vnode.ssFallback) {
-                vnode.ssFallback.el = null
-              }
+              queuePostRenderEffect(() => {
+                if (isInFallback && vnode.ssFallback) {
+                  vnode.ssFallback.el = null
+                }
+              }, suspense)
             }
           }
         }
@@ -577,9 +580,11 @@ function createSuspenseBoundary(
           unmount(activeBranch, parentComponent, suspense, true)
           // clear el reference from fallback vnode to allow GC
           // only clear immediately if there's no delayed transition
-          if (!delayEnter && isInFallback && vnode.ssFallback) {
-            vnode.ssFallback.el = null
-          }
+          queuePostRenderEffect(() => {
+            if (!delayEnter && isInFallback && vnode.ssFallback) {
+              vnode.ssFallback.el = null
+            }
+          }, suspense)
         }
         if (!delayEnter) {
           // move content from off-dom container to actual container

From f6ec7757cd50fff9c325dd192d14a616f24b4a24 Mon Sep 17 00:00:00 2001
From: linzhe141 <1572213544@qq.com>
Date: Wed, 12 Nov 2025 17:40:18 +0800
Subject: [PATCH 2/3] chore: add unit test

---
 .../__tests__/components/Suspense.spec.ts     | 36 +++++++++++++++++++
 .../runtime-core/src/components/Suspense.ts   |  8 ++---
 2 files changed, 39 insertions(+), 5 deletions(-)

diff --git a/packages/runtime-core/__tests__/components/Suspense.spec.ts b/packages/runtime-core/__tests__/components/Suspense.spec.ts
index c6683d6a257..4e8da3288f1 100644
--- a/packages/runtime-core/__tests__/components/Suspense.spec.ts
+++ b/packages/runtime-core/__tests__/components/Suspense.spec.ts
@@ -24,6 +24,7 @@ import {
   shallowRef,
   watch,
   watchEffect,
+  withDirectives,
 } from '@vue/runtime-test'
 import { computed, createApp, defineComponent, inject, provide } from 'vue'
 import type { RawSlots } from 'packages/runtime-core/src/componentSlots'
@@ -2358,5 +2359,40 @@ describe('Suspense', () => {
         `<div>444</div><div>555</div><div>666</div>`,
       )
     })
+
+    test('should call unmounted directive once when fallback is replaced by resolved async component', async () => {
+      const Comp = {
+        render() {
+          return h('div', null, 'comp')
+        },
+      }
+      const Foo = defineAsyncComponent({
+        render() {
+          return h(Comp)
+        },
+      })
+      const unmounted = vi.fn(el => {
+        el.foo = null
+      })
+      const vDir = {
+        unmounted,
+      }
+      const App = {
+        setup() {
+          return () => {
+            return h(Suspense, null, {
+              fallback: () => withDirectives(h('div'), [[vDir, true]]),
+              default: () => h(Foo),
+            })
+          }
+        },
+      }
+      const root = nodeOps.createElement('div')
+      render(h(App), root)
+
+      await Promise.all(deps)
+      await nextTick()
+      expect(unmounted).toHaveBeenCalledTimes(1)
+    })
   })
 })
diff --git a/packages/runtime-core/src/components/Suspense.ts b/packages/runtime-core/src/components/Suspense.ts
index 4731e939409..54bf8edb289 100644
--- a/packages/runtime-core/src/components/Suspense.ts
+++ b/packages/runtime-core/src/components/Suspense.ts
@@ -554,11 +554,9 @@ function createSuspenseBoundary(
               )
               queuePostFlushCb(effects)
               // clear el reference from fallback vnode to allow GC after transition
-              queuePostRenderEffect(() => {
-                if (isInFallback && vnode.ssFallback) {
-                  vnode.ssFallback.el = null
-                }
-              }, suspense)
+              if (isInFallback && vnode.ssFallback) {
+                vnode.ssFallback.el = null
+              }
             }
           }
         }

From 0a9d60a06b297c4b5550f9c6dafc5f279f160e34 Mon Sep 17 00:00:00 2001
From: daiwei <daiwei521@126.com>
Date: Wed, 12 Nov 2025 20:27:56 +0800
Subject: [PATCH 3/3] chore: tweaks

---
 packages/runtime-core/src/components/Suspense.ts | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/packages/runtime-core/src/components/Suspense.ts b/packages/runtime-core/src/components/Suspense.ts
index 54bf8edb289..0c8b6c28e8d 100644
--- a/packages/runtime-core/src/components/Suspense.ts
+++ b/packages/runtime-core/src/components/Suspense.ts
@@ -577,12 +577,9 @@ function createSuspenseBoundary(
           }
           unmount(activeBranch, parentComponent, suspense, true)
           // clear el reference from fallback vnode to allow GC
-          // only clear immediately if there's no delayed transition
-          queuePostRenderEffect(() => {
-            if (!delayEnter && isInFallback && vnode.ssFallback) {
-              vnode.ssFallback.el = null
-            }
-          }, suspense)
+          if (!delayEnter && isInFallback && vnode.ssFallback) {
+            queuePostRenderEffect(() => (vnode.ssFallback!.el = null), suspense)
+          }
         }
         if (!delayEnter) {
           // move content from off-dom container to actual container