Rated 5 out of 5 stars

One idea, change the colour of private tabs so they're easier to distinguish from normal tabs (I know the purple mask icon is there but I sometimes forget about it)
Or just change the favicon to the purple mask

This review is for a previous version of the add-on (0.1.7.3.1-signed). 

See https://github.com/Infocatcher/Private_Tab#styles

Rated 5 out of 5 stars

Convenient

This review is for a previous version of the add-on (0.1.7.3.1-signed).