Current framework isn't compiling LESS properly due to upstream bug with less 3.11.0
https://github.com/less/less.js/issues/3469

Confirmed working with 3.10.3
In the meantime should the less version in package.json be set to 3.10.3 exactly? We should probably consider using package.lock going forward
Seems like a sensible suggestion.
A package-lock might fix both issues.
References:
The above PR is only going to work with master atm and the package-lock will need to be remade after every version number change just before release.
@oliverfoster that second link should be https://docs.npmjs.com/configuring-npm/package-lock-json.html I think
the package-lock will need to be remade after every version number change just before release
How's that done?
$ npm install --package-lock-only will ensure the lock file reflects the installed packages