Gatsby v3: webpack error with "tmp" library (fs.constants / proxy objects)

[nkuehn]

Migrating most of our codebase to v3 was OK and webpack 5 error output was helpful enough to get things fixed.

gatsby is directly depending on the "tmp" library for creating temporary files. That library seems to do something that is causing issues with webpack 5. But the error output is not as helpful as with other libraries that did depend on node APIs:

  14 | const path = require('path');
  15 | const crypto = require('crypto');
> 16 | const _c = { fs: fs.constants, os: os.constants };
     |             ^
  17 | const rimraf = require('rimraf');
  18 |
  19 | /*


  WebpackError: TypeError: 'get' on proxy: property 'constants' is a read-only and non-c
  onfigurable data property on the proxy target but the proxy did not return its actual 
  value (expected '[object Object]' but got '[object Object]')
  
  - tmp.js:16 
    [@my-website]/[tmp]/lib/tmp.js:16:13
```

It makes a very low-level impression and tbh I do neither understand the meaning nor do I have influence on the usage of that library because it's a transitive dependency.  configuring a fallback "false" for the fs module in webpack did not yield a difference. 

Any ideas where to start the process?