What the hell is this? Well, by all means check out the heartbleed.
Looking for TLS extensions on tls://jdavide.it:8443
ext 00043 (supported versions, length=2)
ext 00044 (unknown, length=101)
ext 00051 (key share, length=2)
ext 00043 (supported versions, length=2)
ext 00051 (key share, length=69)
ext 00010 (supported_groups, length=18)
TLS extension 15 (heartbeat) seems disabled, so your server is probably unaffected.