[en]

Maybe not the best solution, but for the js CDN of Google, I'am using a self hosted mirror with this list https://github.com/euh/googleapis-libraries-list

Unfortunately in HTTPS, I need to bypass HSTS protection and for Firefox it's annoying (I don't know for Chrome).

For the fonts I tried to create a self hosted mirror too, but Google does not offer to download exactly the exact fonts they host.

[annnnd]

How is that possible? You just download them and save them on your server... Unless you are worried about breaking some TOS?