Yes it's right, during the last weeks a lot of work has been spent on this site and the website itself never changed. It started with the idea to get this website secure by https / SSL and to make it faster by usage of http2. Having thought about it and having remarked the new Ubuntu-version I decided to upgrade the operating-system Ubuntu first. As direct impact the option to use one of two different PHP-Versions had to be included because the PHP-Version in the new Ubuntu never works well with the older TYPO3-Version-Tree we still use on our server.
Afterwards I changed from the server-software apache-web-server to nginx-webserver because I read that implementation of http2 is easier there. Using http2 is directly combined with the requirement https / SSL, so the latter one was the next step to implement. While this requires usage of a certificate which mostly is charged with ~ 100-200 $ a year there exists a new free option with letsencrypt alias certbot. Implementation of letsencrypt alias certbot was quite easy, just concerning several subdomains still some struggling occured, which was primary related to future-update of the certificates.
All right, now the site is running with https / SSL and free certificate from letsencrypt.org and enabling http2 in nginx was concerning required time not remarkable at all.
As next step I used the browser-extension yslow to speed up the page-loading. Activating gzip to compress the data, combining and minifying some scripts and the site is running with 100 of possible 100 points.
Congratulations and what's coming next?
Beside improvable content the tests on www.google.com/webmasters/tools/home are a bit harder than of Yahoo and there is still some time to spend to get better results. Nevertheless after small changes the page was judged already as mobile-friendly, this improves the rank in any search-results and surly is a benefit for any page-visitors.
There are still options to increase security concerning website and SSL-certificate which can be checked i.e. on www.htbridge.com/ssl/. Until no user-input and no user-accounts are offered on this page there is no emergency.