Vue version

3.5.31

Link to minimal reproduction

https://github.com/Gabriel-SPassos/vue-teleport-regression

Steps to reproduce

git clone https://github.com/Gabriel-SPassos/vue-teleport-regression
cd vue-teleport-regression
npm install
npm run dev

1. Open http://localhost:3000
2. Click "Go"
3. Check the browser console

What is expected?

Navigation to Page B completes without errors. Teleported elements from the previous page are cleanly unmounted.

What is actually happening?

Dev mode (npm run dev):

RangeError: Maximum call stack size exceeded
    at queuePostFlushCb
    at queueEffectWithSuspense
    at Object.process
    at flushPostFlushCbs
    at flushJobs

Infinite recursion in the scheduler — deferred Teleport post-flush callbacks create a loop between queueEffectWithSuspense and flushJobs.

Production mode — observed in a real-world Nuxt app:

TypeError: Cannot destructure property 'bum' of 'y' as it is null.
    at unmountComponent
    at unmount
    at Object.remove (Teleport.remove)

The page freezes — URL updates but the UI does not re-render.

Vue 3.5.30: No errors in either dev or production mode. Navigation works as expected.

System Info

System:
  OS: macOS 15.5
  Node: v20.19.0
Binaries:
  npm: 10.8.2
npmPackages:
  vue: 3.5.31
  nuxt: ^4.1.1

Any additional comments?

Scenario:

• Nuxt 4 app with SSR enabled
• Page A (index.vue): await useFetch() in setup (triggers Suspense wrapping by <NuxtPage>), two <teleport to="body"> blocks each containing a <Transition> wrapping v-if content with nested child components, reactive state changes after navigateTo() (clearing items array + resetting a flag in finally)
• Page B (page-b.vue): has async setup (await useFetch(...)) and its own <teleport to="body">
• The crash occurs during the Suspense branch swap — deferred Teleport post-flush callbacks create an infinite loop in the scheduler

Candidate PRs merged between 3.5.30 and 3.5.31:

The interaction between #8619 (deferring Teleport operations when parentSuspense.pendingBranch exists) and #9392 (changing Suspense unmount timing when wrapped in Transition) appears to create this issue during Nuxt's page navigation cycle (Suspense + Transition + Teleport).

Workaround: Pin vue to 3.5.30:

{
  "overrides": {
    "vue": "3.5.30"
  }
}