LH 1397 then 4Y 900 at Frankfurt
Prague → Frankfurt am Main → Dubrovnik
Timetable, Frankfurt am Main time
16:00LH 1397 from Prague at the gate
09:254Y 900 to Dubrovnik leaves the gate
17 h 25 apart on the timetable, overnight
4Y 900 leaves 17 h 25 after LH 1397 arrives on the timetable: more than half a day, so not a connection we count.