Octicons.css not in-lined like other style sheets when using `--export`

I installed grip via pip install grip grip -V returns Grip 4.5.2

When I use grip in cmd and view the webpage, the source shows several stylesheets including octicons.css. everything works fine

When I use grip --export and open the exported .html, all of the stylesheets are inlined EXCEPT for octicons.css.

This results in a 404 on loading the page