lethean-vpn$ ./configure.sh --client
Incompatible version of haproxy! You need 1.6.x, 1.7.x, 1.8.x or 1.9.x version for now.
HA-Proxy version 2.2.3-2 2020/09/09 - https://haproxy.org/
Status: long-term supported branch - will stop receiving fixes around Q2 2025.
Known bugs: http://www.haproxy.org/bugs/bugs-2.2.3.html
Running on: Linux 5.8.0-50-generic #56-Ubuntu SMP Mon Apr 12 17:18:36 UTC 2021 x86_64
OS: Ubuntu 20.04