Rated 5 out of 5 stars

First of, thank you for a very useful, well-crafted add-on.
A relatively minor issue: In the toolbar menu, that list of sites one can enable/disable, could you please put those inside a submenu/folder so that the menu isn't so tall?
Because of it, right now I can't place the TZP icon exactly where I want to have it within Firefox's three-bar menu (below some 'regular' Firefox buttons + several other add-ons buttons I prefer to keep 'together' due to their complimentary focus). I'm on a large monitor and even then (if placing the TZP icon where I ideally want to have it) I'd still need to scroll the TZP menu just to reach 'Preferences', where I just want to have quick access without fuss. (I access the Preferences regularly, because for certain sites I like to temporarily turn on 'Add to History'; I'm aware of Hotkeys, not a fan in general)
I realise this is a bit of a nitpick, but it's still quite bothersome all the same, and honestly it would make the TZP menu a lot more streamlined regardless of my particular situation, so I'm hoping you'll want to put it on your to-do list.

This review is for a previous version of the add-on (3.7). 

It's a good suggestion, thanks. Here's something else which may help: when a pop-up is displayed, press the 'p' key to open Preferences.