I have updated Apache2 on Debian Jesie using testing repository
https://www.shivering-isles.com/http-2-getting-ready-on-debian-with-apache2/
now i have:
Server version: Apache/2.4.27 (Debian)
Server built: 2017-09-23T22:08:01
an2mod http2 ..done
ls -la /etc/apache2/mods-enabled
lrwxrwxrwx 1 root root 28 Sep 25 16:42 http2.load -> ../mods-available/http2.load
/etc/apache2/conf-available/http2.conf .... edited
....
but checking https://www.tecnocroci.it HTTP2 doesn't work