statt:
var original = "user hashimoto has two dogs";
var pos = original.lastIndexOf("has");
var neu = original.substr(0,pos) + original.substr(pos+3);
muss es lauten:
var original = "user hashimoto has two dogs";
var pos = original.lastIndexOf("has"); 
var neu = original.substr(0,pos) + original.substr(pos+1);
 nicht angemeldet
 nicht angemeldet Rolf b
 Rolf b Matthias Apsel
 Matthias Apsel TS
 TS Gunnar Bittersmann
 Gunnar Bittersmann JürgenB
 JürgenB Jonny 5
 Jonny 5 Matthias Scharwies
 Matthias Scharwies