403 jupyter_server blocking request with no referer blocking request with unknown origin

I am doing a streamlit project. I am using the streamlit.components to load a CSS file into an HTML script so that it can render on the browser. Unfortunately, only the HTML text displays but the CSS fonts and background image do not show.

I checked by running the script by running it offline from the desktop and it worked well.

l later saw this “403 jupyter_server blocking request with no referer; blocking request with unknown origin”. It was targeting my CSS images. Why? I need to resolve this so that I can build my web app fully.

I am using JupyterLab and Opera browser.