Fixed decrement-underflow occurring when editing the first ever message.
Fixed decrement-underflow occurring when editing the first ever message.

ohAitch/arvo,urbit/urbit,ngzax/urbit,belisarius222/arvo,ngzax/urbit,jfranklin9000/urbit,joemfb/arvo,ngzax/urbit,urbit/urbit,cgyarvin/arvo,ngzax/urbit,urbit/urbit,urbit/urbit,ngzax/urbit,jfranklin9000/urbit,ohAitch/arvo,belisarius222/arvo,urbit/urbit,ngzax/urbit,jfranklin9000/urbit,urbit/urbit,Fang-/arvo,urbit/urbit,cgyarvin/arvo,jfranklin9000/urbit,ngzax/urbit,jfranklin9000/urbit,jfranklin9000/urbit,jfranklin9000/urbit,joemfb/arvo