Prefbar doesn't show Rated 5 out of 5 stars

After I moved the toolbars, there is a small problem with a PrefBar toolbar - it doesn't show up after restarting Firefox and I have to make Rignt Mouse Click: Customize: OK on the toolbar to restore it.
Prefbar extension link:
https://addons.mozilla.org/en-US/firefox/addon/67148/

This user has a previous review of this add-on.