Loads links in new tabs, by conditions. This provides only following features:
* Always opens new tab for links to other websites. (Or, loads any link in new tab.)
Yes, they are included in famous tab-related addons, Tab Mix Plus etc. This is for people who want only these features (and don't want other needless features.) And, there is similar addon DomainTab ( https://addons.mozilla.org/firefox/addon/13906/ ).
By the way, this is originally develped as a part of another addon Tree Style Tab ( http://piro.sakura.ne.jp/xul/_treestyletab.html.en ). If you install both addons, new tabs from links will become children of the current tab.