I put in my site and it gave me a red cross for "Hosting", on hover it said "GitHub Pages". But my site isn't hosted on GitHub Pages.
Expanding "Details", the URL that is hosted on GitHub Pages is... a different website? There's merely a hyperlink to it on my website.
It also says I'm using "self-hosted" fonts - but I don't think I'm doing that at all? I'm just using the browser's fonts. Using non-standard fonts is a bad idea because it causes the content to either be invisible until the font is loaded, or else it initially shows in a fallback font and then the text all jumps when the font is loaded.
Meanwhile I get a green check for CDN - presumably because I'm not using Cloudflare, but I am using CloudFront which is AWS.
So the tool's a good idea, but currently very inaccurate.
Meanwhile, mine is actually hosted on GH pages and I get a green mark and a perfect 100% score.
Funny, I checked a blog I host on github pages and it says "not detected" for hosting.
It also says my website is hosted on GitHub pages, although it’s served from a hetzner server.
EDIT: on further inspection: I get both a red cross AND a green check mark for hosting. So it’s somehow indicating both GitHub and hetzner. Maybe it’s because I merely link to GitHub?