Update firstpush

buildroot/share/git/firstpush

 
 git push --set-upstream origin HEAD:$BRANCH
 
-which xdg-open >/dev/null && TOOL=xdg-open
-which gnome-open >/dev/null && TOOL=gnome-open
-which open >/dev/null && TOOL=open
+OPEN=$(echo $(which gnome-open xdg-open open) | awk '{ print $1 }')
 URL="https://github.com/$FORK/$REPO/commits/$BRANCH"
 
 if [ -z "$OPEN" ]; then