I’ve just installed GRAV as a docker container on my Ubuntu server.
I tried to install a new theme too, but during the installation process a warning message popped up:
I don’t know what it is exactly about. Could the problem be due to the fact that my connection is behind CGNAT?
The theme / online template does not exist … its a 404 error… so I think you might have a very old of theme, that has been abandoned.
Try outside your docker image , you will see.
GitHub - getgrav/grav-theme-photographer: Photographer Theme for Grav - Modern photography portfolio.
This is a link for the official photographer theme. Is this the theme you need.
It should be able to install via searching the theme section.