BT 877 then FR 4587 at Barcelona
Tallinn → Barcelona → Porto
Timetable, Barcelona time
10:30BT 877 from Tallinn at the gate
22:55FR 4587 to Porto leaves the gate
12 h 25 apart on the timetable
FR 4587 leaves 12 h 25 after BT 877 arrives on the timetable: more than half a day, so not a connection we count.