Rated 4 out of 5 stars

A good addon, does what it says it does. Also the most reliable addon for minimize to tray functionality.

But please also consider adding the following functions:
(1) Transparent windows
(2) Clickthrough windows
These two features will allow us to play a youtube video or read text on the bottom window while we continue our work or take notes on the top window
(3) Dock firefox window to the monitor edge. To be autorevealed or autohidden on moving the mouse cursor to the screen's edge.