The tutorial at the cesium webpage, is that up to date?
It differs a bit from the example at:
I tried to update the webpack example above for webpack 5 (I think I need to use this version for jupyterlab), PR available at Updates for using webpack 5. Please review by petrushy · Pull Request #25 · CesiumGS/cesium-webpack-example · GitHub
The standalone example seems to work with that PR, but the integration into other application is failing.
Somehow I think that the CopyWebpackPlugin files are not included in the final output. They are visible in the dist directory but somehow not included in the webpack or are they served directly from the dist directory?