Match 0 or 1 usercontent in RawGitHub regex
Match 0 or 1 usercontent in RawGitHub regex

christophelec/nbviewer,AlfiyaZi/nbviewer,AlfiyaZi/nbviewer,iamjakob/nbviewer,iamjakob/nbviewer,Jay-Oh-eN/nbviewer,bollwyvl/nbviewer,christophelec/nbviewer,Sage-Bionetworks/nbviewer,imsparsh/nbviewer,Jay-Oh-eN/nbviewer,bollwyvl/nbviewer,thomasyu888/nbviewer,roxyboy/nbviewer,roxyboy/nbviewer,Sage-Bionetworks/nbviewer,imsparsh/nbviewer,thomasyu888/nbviewer