mdx js loader: paths must be valid file:// URLs (windows only)

[chrisweb]

Link to the code that reproduces this issue

https://github.com/chrisweb/nextjs_mdx-js-loader_windows_reproduction

To Reproduce

1. clone the repo (git clone https://github.com/chrisweb/nextjs_mdx-js-loader_windows_reproduction.git)
2. install the dependencies (npm i)
3. run the development server (npm run dev)

Current vs. Expected behavior

if you are on windows you will now get an error in your terminal and can also see it if you open localhost:3000 in your browser

Provide environment information

Operating System:
  Platform: win32
  Arch: x64
  Version: Windows 10
Binaries:
  Node: 23.5.0

Which area(s) are affected? (Select all that apply)

Markdown (MDX)

Which stage(s) are affected? (Select all that apply)

next dev (local)

Additional context

bug is windows specific, turbopack needs to be enabled, mdx support in next.config using @next/mdx, using mdx plugins where name is a string and options need to be serializable (this example has no options for simplicity)

[himself65]

Related: nodejs/node#31710