There seems to be a difference in the splitting of a Perek in Pirkei Avos. On sefaria the perek I am referring to is Perek 3 where the Perek in Sefaria groups certain Mishnayos in that Perek together unlike Artscroll which instead of being 18 Mishnayos, it is 23. One Mishna for example in the Artscroll is 3:19 whilst on Sefaria it is 3:15.
Is there any reason for the split and difference between these two versions?