Dicko and Costa spent a season together at Wolves, who loaned the latter to Leeds on Wednesday, before the former moved to Hull.
And after Costa thanked his parent club, who have already agreed to sell him to the Whites next summer, Dicko was among those to sent their best wishes.
But the Mali international, who is understood to live in the West Yorkshire city, cheekily added: "See you in Leeds", alongside the 'Eyes' emoji.
Leeds were one of the Championship's most wasteful sides in front of goal last season, and could look to strengthen at centre forward this summer.
Dicko, though, is perhaps unlikely to be among those considered by the Whites, having scored just seven goals in 50 games for Hull.
The 27-year-old, for whom Wolves are reported to have received around £3.5 million in 2017, recently entered the final 12 months of his contract.
Would the former Wolves man be a good addition for Leeds?
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