Customize Theme locally fail to load admin_jquery

[bourroush]

When working locally, if you click Customize Theme, the sections on the left sidebar are not lodaing, due to a javascript error. But if I'm doing a yarn build -- --deploy, and if the website is pulling its files from shopify instead of localhost:8080, then there is no error.
http://cloud.godynamo.com/0z1Q1R2u3j3k

[nddery]

(edited) Shopify Webpack style loader seems to output <link type="text/css" rel="stylesheet" href="blob:https://dynamomtl.myshopify.com/17b0ac9c-bf91-46a4-80d0-085980101e3c"> in the layout head ({{ content_for_head }}), while running yarn serve, but not when building. Not sure why. For some reason, it ignores output.publicPath (which is correctly set to https://localhost:8080/).