Correct link to documentation about key codes
Set special attribute to indicate, that selected tab is private
Usage: #main-window[privateTab-selectedTabIsPrivate]
We currently have "usePrivateWindowStyle" preference, so this is an alternative for #main-window[privatebrowsingmode="temporary"]
(related to #40)
Add information about "privateTab-selectedTabIsPrivate" attribute
(related to #40)
Update copyright year