I've created a very small tool to keep our domainname for images hosted on firebase for free (free plan Firebase/Cloudflare).

Advantages:

- No bandwidth usage on your Firebase (free) plan for cached images
- Routing can be done to multiple (free plan) firebase projects to keep costs at zéro
- Keep the SEO advantage by keeping domain.com/img/... instead of pointing to Googlestorage domains

I've used and deployed this tool for the 1616.be project