Rated 4 out of 5 stars

Very good add-on. MUCH better than any other note-taking add-on that I've tried. Two problems however:
(1) If you open it in the sidebar (for example), make some changes, save those changes, close the sidebar, then open it in a "float window", it will lose the changes you made. Apparently, all three ways to display the notes are loaded at the same time (when Firefox starts rather than when the notes are opened and displayed???), so changes made in one display mode do not apply to the other display modes.
(2) I tried the development version to see if problem #1 had been fixed, but I found a new problem instead - the captions on the note tabs do not display correctly.

This review is for a previous version of the add-on (0.7.2.1-signed). 

Sorry, but I can't reproduce your problems. I'm using QuickNote day by day and never experienced behavior described in the point 1. Development versions are development versions...