Worker fails on local dev

It works on distribution build though... seems to be some reference to undefined window generated in webpack somewhere... will likely just fix by updating webpack-dev-server and webpack and eventually they'll fix it ;)

Start by reproducing the worker failure in the local development build and comparing it with the distribution build. Inspect the webpack and webpack-dev-server configuration or generated output for the undefined window reference. Done means the worker runs successfully during local development without regressing the distribution build.

Written by the indexing model from the issue text.