This service is a reverse proxy preventing your IP from being tracked by 3rd-party services providing webfonts for use in websites and web applications.
This page provides information on this proxy and how to use it. In addition, it's smoke testing the reverse proxy, too.
... you wouldn't see fancy-style headlines and a sans-serif font for run text. All text on this page would look like this.
The reverse proxy is improving GDPR compliance of consuming websites and web applications by redirecting incoming requests to an actual web font provider. This way, personal information on a visitor to a website or web application is kept hidden from those web font providers. For them, all requests originate from this proxy.
However: When using this proxy with any other site or application, the proxy is replacing those web font providers with us. With regard to the GDPR compliance, this isn't any better unless we've signed a GDPR-compliant data processing agreement with you. Without it, we are not any more trustworthy than those.
You don't need any proxy for webfonts if you can host them yourself as part of your website or application. With regard to GDPR, this is the best option eventually.
If you can't provide the fonts as part of your website or application, you can still create a proxy like this one yourself:
When intending to use a Google webfont, replace hostname fonts.googleapis.com in URL with google-fonts.cepharum.de.
On self-hosting this proxy, use whatever hostname you've set up for Google Fonts in your case, instead.
A Google font is used for styling headlines on this page.
When intending to use an Adobe TypeKit webfont, replace hostname use.typekit.net in URL with typekit.cepharum.de.
On self-hosting this proxy, use whatever hostname you've set up for Adobe TypeKit in your case, instead.
An Adobe TypeKit font is used for styling runtext on this page.