Try this version.... Rated 5 out of 5 stars

Thanks Sabine! Finally got them re-ordered thanks to this. (running TB 3.02)
http://downloads.mozdev.org/xsidebar/mods/folderpane_tools-0.6-mod.xpi
works perfect. To use in Tbird browse to http://downloads.mozdev.org/xsidebar/mods/ then look for folderpane_tools-0.6-mod.xpi , right click/ save as , yadda, yadda, yadda

This review is for a previous version of the add-on (0.0.5.1).