I have tested nagios-plugins v 2.4.5 check_http. Based on the help section in the CLI it still supports all but TLSv1.3:
Are there any plans for adding TLSv1.3 there as in 2024 it can become standard for many cases.-S, --ssl=VERSION[+]
Connect via SSL. Port defaults to 443. VERSION is optional, and prevents
auto-negotiation (2 = SSLv2, 3 = SSLv3, 1 = TLSv1, 1.1 = TLSv1.1,
1.2 = TLSv1.2). With a '+' suffix, newer versions are also accepted.
Maybe there is alternative how to check HTTPS server running only TLSv1.3 which I can use - will be also useful.
Thanks!