Thank you for checking.

Problem is misconfigured DNS:

   1 blog.ffwll.ch:
   77 bytes, 1+2+0+0 records, response, authoritative, noerror
   query: 1 blog.ffwll.ch
   answer: blog.ffwll.ch 3600 CNAME danvet.github.io
   answer: danvet.github.io 3600 A 192.64.147.142

I mistook 192.64.147.142 as the correct IP address.

Try that one with curl, firefox or elinks.

Correct address is 151.101.53.147.