Vue.js unexpected token in browser but npm run build with no errors
Open the URLs of the scripts each on a different tab (or check the network tab of the developer tools), those URLs are probably returning a 404 (or some other error code) and a HTML error page.
So your code tries to parse those HTML error pages as JavaScript code, thus yielding that error.
It gets Uncaught SyntaxError: Unexpected token < because it tries to parse the HTML content (e.g. <html> ...) as JavaScript code.
Run the snippet below and see the error at the console.
<script type=text/javascript src=https://stackoverflow.com></script>
Check the console: "Uncaught SyntaxError: Unexpected token <"