Puntuado con 4 de 5 estrellas

Is it possible to make this addon available for earlier versions, for example for FF 16 ?
It keeps only verical position or horisontal too?
In this case it can be very useful for bookmarks that should be opened in sidebar
Unfortunately I can not check this because this addon is not available for my FF version

Esta valoración es de una versión anterior del complemento ( 

I don't think it possible support 16 because I used jetpack.
It use both x and y positions.
Just in case you can find source this plug-in here: