Import of headless.conf.js breaks in Windows due to incorrect pathname

[uglyrobot]

Describe the bug

Using NextJS 14.2 in Windows dev environment. Throws errors that it can't import the config file, and the pathname in the errors is missing the slashes: c:somethingSomethingDirheadless.config.js

I confirmed that merging the configs with withHeadlessConfig() the output is ok, so loading the config in next.config.js is working fine, it's the loading in the package that breaks.

Steps to Reproduce

• Run npm run dev in Windows
• Get compile errors

Screenshots, screen recording, code snippet

No response

Environment information

NextJS 14.2.13 Windows Nodejs 20

WordPress information

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