Run uzbl only if a bookmark was selected

dotfiles/i3/config

 bindsym $mod+Return         exec "urxvt"
 bindsym $mod+Shift+Return   exec "urxvt -pe 'default,tabbed'"
 bindsym $mod+b              exec "ub"
-bindsym $mod+Shift+b        exec "eeini www.ini       | eedmenu --split = | xargs ub"
+bindsym $mod+Shift+b        exec "eeini www.ini       | eedmenu --split = | xargs -r ub"
 bindsym $mod+Shift+f        exec thunar
 bindsym $mod+Shift+o        exec "urxvt -e mocp"