How dose the error happen: "

[youngchan1988]

Reproduction

This is not a reproducible issue. I want to know how to locate this issue. And possible causes of this issue.

System Info

System:
    OS: macOS 15.6.1
    CPU: (16) x64 Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz
    Memory: 418.84 MB / 32.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 22.19.0 - ~/.nvm/versions/node/v22.19.0/bin/node
    Yarn: 1.22.4 - /usr/local/bin/yarn
    npm: 10.9.3 - ~/.nvm/versions/node/v22.19.0/bin/npm
    pnpm: 9.14.4 - /usr/local/bin/pnpm
    bun: 1.2.12 - ~/.bun/bin/bun
  Browsers:
    Chrome: 140.0.7339.185
    Safari: 18.6
  npmPackages:
    @react-router/dev: ^7.9.1 => 7.9.1 
    @react-router/fs-routes: ^7.9.1 => 7.9.1 
    @react-router/node: ^7.9.1 => 7.9.1 
    react-router: ^7.9.1 => 7.9.1 
    vite: ^6.3.3 => 6.3.5

Used Package Manager

pnpm

Expected Behavior

No the exception.

Actual Behavior

This exception sometimes occurs when open our website.

[github-actions]

👋 @youngchan1988, we use the issue tracker exclusively for bug reports and feature requests. However, this issue appears to be a support request.
For usage questions, please use Stack Overflow or Discord where there are a lot more people ready to help you out, or post a new question in the Discussions tab of this repository.
Please feel free to clarify your issue if you think it was closed prematurely.

[github-actions]

To align with our new Open Governance model, we are now requiring that all issues have a minimal and runnable reproduction. This should help us to focus on actionable issues and be more responsive to newly filed issues.

To get this re-opened, please add a reproduction to the Issue description and tag @brophdawg11 or @brookslybrand in a comment so we can re-open.

Or, if this was closed by mistake and there is a valid reproduction, please ensure that it is linked in the Issue description and and tag @brophdawg11 or @brookslybrand in a comment so we can re-open.

If you have any questions, you can always reach out on Discord. Thanks again for providing feedback and helping us make React Router even better!