Hey man, thanks for the kind words.

To start with i’m pretty sure this is an error in your configuration judging by the message you get.

This LESS “class” simply imports 2 files as seen in the code below

.loadUIOverrides() {
  @import (optional) "@{themesFolder}/@{theme}/@{type}s/@{element}.overrides";
  @import (optional) "@{siteFolder}/@{type}s/@{element}.overrides";
}

so it being undefined means that for some reason, webpack cannot find it where it looked for it. Please check whether your alias in webpack is correct or whether you mistyped something. Also check out the repo that has a working example and check not only if there are any code differences, but also if you can have it installed and bundled locally.

I’ll be waiting for your response in order to dig deeper into the issue.

Cheers :)