When using MiniCssExtractPlugin with css modules and typescript packages, there can be an issue where the modules have a dependency that never completes processing as it cannot be picked up - i.e. _activeTasks === _parallelism in webpack Compilation.js.

This is ok for smaller projects, where the default parallelism of 100 will hide the bug, but with many packages in large projects you can run into the issue consistently.

1. Clone repo and install dependencies
2. Run yarn test, notice that it will never complete (stalls at 28%)
3. Take a look at webpack.config.js, you can toggle either parallelism or experimentalUseImportModule and re-run yarn test and notice it works.
4. Run yarn clean to remove the output and rebuild if necessary.