Loading 3d model in Content Editor isn't working

It seems that in Content Editor the local webserver used for render didn't serve all files in Media directory, see image with console :
There is multiple retries in the widget source code, that why multiple FileError appears.

If someone has an idea of how file can be serve directly in Content Editor webserver, it would be nice !

Start with the widget source code and the local webserver used by Content Editor, then inspect how files in the Media directory are served and review the console errors shown in the issue. Done means the webserver serves all required Media files so the 3D model loads without the repeated FileError retries.

Written by the indexing model from the issue text.