in https://github.com/coreui/coreui-free-vue-laravel-admin-template/blob/master/coreui/public/index.html
in the bottom, there is "app.js" script hardcoded into that index.html

however, on each dev build, there is additionally appended that again, which ends up in duplicated source code, like this screenshot:
https://i.imgur.com/SxWP7B2.png

this issue might be in other CoreUI templates too.