[Vuejs]-Vue.Js | Components isn't working. | Unknown custom element: <image-upload>

Have you tried to add a : to your vue component.

<image-upload :img-url="{{url('img/user.png')}}"></image-upload>

Does the Vue component appear in the Vue.js inspecter?

https://chrome.google.com/webstore/detail/vuejs-devtools/nhdogjmejiglipccpnnnanhbledajbpd