AZ 863 then FR 4891 at Fiumicino
Tunis → Rome → Catania
Timetable, Rome time
12:50AZ 863 from Tunis at the gate
12:15FR 4891 to Catania leaves the gate
23 h 25 apart on the timetable, overnight
FR 4891 leaves 23 h 25 after AZ 863 arrives on the timetable: more than half a day, so not a connection we count.