FR 652 then FR 1791 at Lisbon
Dublin → Lisbon → Luxembourg
Timetable, Lisbon time
20:25FR 652 from Dublin at the gate
15:00FR 1791 to Luxembourg leaves the gate
18 h 35 apart on the timetable, overnight
FR 1791 leaves 18 h 35 after FR 652 arrives on the timetable: more than half a day, so not a connection we count.