Rated 5 out of 5 stars

Very much like the toolbars, however there's a small issue with running under Windows 10. Running maximised the menu bar is too slim and chops the words off slightly and the tabs are not visible. Also the standard buttons on the top right corner look out of place from a colour mismatch.
The Privacy icon in the Options dialog box is also missing.

This review is for a previous version of the add-on (1.3.0). 

Version 1.4.2 fixes these problem, and quite a few others. I also recommend the Titlebar Tabs Cleaner extension to completely restore the classic titlebar look. Hope you'll try it out!