Unfinished, but has potential Rated 3 out of 5 stars

I am really glad this kind of extension is finally on Firefox!
However, it's implementation is not so good.
1) Indicator
A great option would be forcing it instead of tab favicon, like Opera. If you don't want that, instead of address bar favicon at least. If not favicon, put a text on the tab saying [PRIVATE], [P] or simply different color, changeable in settings. Some themes/extensions make the underline hard to see so there should be a option to change it.

2) Access
Access isn't that good either. Well, you have toolbar button... but that's it. There should be a way to combine it with normal new tab button, for example on right click (menu), middle click (instant), right click (instant).
Toggling a tab between private and normal mode is simply useless.Either way there is something on your history already, even if you just open a new tab.

3) More features
You could add more features like certain domains become private automatically or you can't mix (drag in between) normal and private tabs, just like normal and pinned tabs can't be mixed.

Reply:

1) Great you had those existing at least :D
Worked well, thanks.

2) :)

3) Alright.

This review is for a previous version of the add-on (0.1.3). 

> 1) Indicator
Unfortunately complex styles is less compatible with other themes/extensions.
You can find some styles for userChrome.css/Stylish here: https://github.com/Infocatcher/Private_Tab#styles

> 2) Access
> There should be a way to combine it with normal new tab button
This makes sense, I'll think about it.

> 3) More features
> like certain domains become private automatically
See my reply here:
http://forums.mozillazine.org/viewtopic.php?p=12922835#p12922835

> or you can't mix (drag in between) normal and private tabs, just like normal and pinned tabs can't be mixed.
I don't like to override built-in drag and drop functions, it's difficult to implement and maintain and may be impossible to do it restart-less (troubles with undo ability).