Rated 2 out of 5 stars

Although the PrefBar add-on web page states: The bar itself may be moved using the browser built-in "toolbar customize" feature to anywhere you like (even in foreign toolbars, next to the menubar, ...).
This is no longer an offered feature in the 5.x version. Reverting to the 4.3.2 version until the developer catches this issue seems to be the only solution for getting back browser screen space

This review is for a previous version of the add-on (5.1.0).