Vue version

3.5.19

Link to minimal reproduction

https://github.com/Milkdown/milkdown/tree/a392b37735a8859c05dcce36ecc84a1ef7bc2c77

Steps to reproduce

1. Clone the repo
2. Run pnpm install
3. Run pnpm build:tsc
4. Run pnpm -F @milkdown/storybook run build
5. Run pnpm -F @milkdown/storybook run serve

Open the preview link, choose Component/Code Block or Crepe/Empty (In fact all crepe components dead).

Observe the error:

What is expected?

Vue should work without the compile-time flags.

https://vuejs.org/api/compile-time-flags#configuration-guides

According to the documentation, these are optional flags.

What is actually happening?

An error is thrown.

System Info

System:
    OS: macOS 15.6.1
    CPU: (12) arm64 Apple M3 Pro
    Memory: 198.64 MB / 36.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 22.18.0 - ~/.local/state/fnm_multishells/81316_1755955224967/bin/node
    npm: 10.9.3 - ~/.local/state/fnm_multishells/81316_1755955224967/bin/npm
    pnpm: 10.15.0 - ~/.local/state/fnm_multishells/81316_1755955224967/bin/pnpm
    Watchman: 2025.05.26.00 - /opt/homebrew/bin/watchman
  Browsers:
    Chrome: 139.0.7258.139
    Safari: 18.6

Any additional comments?

3.5.18 works fine.