Very Useful - Hide Title Bar, small and efficient. Rated 5 out of 5 stars

Tip: Turn on "Title in Status bar" - then you can remove the "Title Spacer" from the top. Cleaner look and good use of status-bar with no loss of functionality (hover over a link and it shows up as usual). Cannot praise this extension enough. The "M" Button can be lost in a dark theme.

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