oops... I didn't seen it was for version 12 ... strange anyway we could do it in version 12 and not in version 29

Hello
I can't move icons extensions from the left to the right.
http://inft.ly/3iL4BTn

I found an article ( http://www.opera.com/help/tutorials/personalize/ui/#toolbar ) that explains how to proceed, it's written this: To do this, Ctrl-click the toolbar and select “Customize”, but nothing happens when I click on the toolbar …

Can someone explain me how to proceed?

Thank you