authentication key of extras repository is missing

Thank you for taking the time to make Ubuntu better. Since what you submitted is not really a bug, or a problem, but rather an idea to improve Ubuntu, you are invited to post your idea in Ubuntu Brainstorm at http://brainstorm.ubuntu.com/ where it can be discussed, voted by the community and reviewed by developers. Thanks for taking the time to share your opinion!

If the extras repo was offered *by the installer* and not added by the user, then it does indeed seem like a bug.
Why would the installer offer to install supported repos, and then not do it?

Thanks for your response Ian, I'm glad you're seeing this as a bug, because it's exactly as you think. Discussing this problem on ubuntu brainstorm didn't help either, they said it's not an idea. I can agree with that, but why is Fabio then suggesting to discuss it there?

I'm sorry to say so, but his answer didn't help me (it seemed not a good idea to post it in Ubuntu brainstorm), but worse, the Ubuntu community now has one month less to solve the problem. And being the release cycle every six months (which I honestly think is far too short, to make something new and iron most of the bugs out) this seems, to me at least, valuable time wasted.