[whynot]

Ca c'est une idée qu'elle est bonne :

Tabs Open Relative is an extension for Mozilla Firefox which causes new tabs to be opened to the right of the current tab, rather than at the far right of the tab bar.
In the case where several new tabs are opened in a row without switching tabs, each subsequent tab will be opened to the right of the previous one.
For example if you have three tabs open, [A], [B] and [C], where the current tab is [B], then you open three more tabs, [1], [2] and [3], you'll get:
[A] [B] [1] [2] [3] [C]