I have done as you have suggested and still having problems. See screen shot: http://prnt.sc/dwuz9e
When I update the publicPath to "/", it appears to work (no errors in browser), but the Header.css reference to background: #eee url(/bbaeb5f32b7042f0def39648a1d111b9.png) center - does not work. The header is all grayed out. It appears to me there is a bug with the output in webpack.config.dev.js or it is just not intuitive. I've tried a number of different variations. Also I think it's strange that the png gets put right in the root directory - this seems messy. Would be nice if it were in it's own ignored folder (ie: src).