Where does “dłudzko” come from?

dłudzko (Polish) comes from Polish dłudzki, from Polish długi, from Old Polish długi, from Proto-Slavic dь̀lgъ, from Proto-Balto-Slavic dílˀgas, from Proto-Indo-European dl̥h₁gʰós — long.

Ancestry of “dłudzko”, step by step

Step	Language	Word	Meaning
1	Polish	dłudzki	—
2	Polish	długi	long; nominative/accusative/vocative plural of...
3	Old Polish	długi	long
4	Proto-Slavic	dь̀lgъ	long
5	Proto-Balto-Slavic	dílˀgas	long
6	Proto-Indo-European	dl̥h₁gʰós	long

Every word from Proto-Indo-European dl̥h₁gʰós →Every word from Proto-Balto-Slavic dílˀgas →Every word from Proto-Slavic dь̀lgъ →