Rated 5 out of 5 stars

Just perfect.
I would love if there is a button at the 'New tab' page (about:newtab) to convert it to a Private tab.
I really like keyboards shortcuts but I'm using Ubuntu and I use Ctrl+Alt+T to open my terminal. It will be nice if the user could set the hotkeys.
I would love to see either of the both features.

This review is for a previous version of the add-on (0.1.7.1-signed). 

> I would love if there is a button at the 'New tab' page (about:newtab) to convert it to a Private tab.
I'll think about this.

> It will be nice if the user could set the hotkeys.
You can change extensions.privateTab.key.* preferences on about:cinfig page, see notes in
https://github.com/Infocatcher/Private_Tab/blob/0.1.7/defaults/preferences/prefs.js#L9-L16