User blog comment:Dopp/Technical Update: September 13, 2011/@comment-188432-20110919172152

Page Layout Builder isn't accessible at all using only Opera 10.63.

When you attempt to start a new layout, you get the tutorial lightbox. No lightboxes work at all in Opera 10.63. Usually you can click anywhere on the screen and the lightbox will at least go away. That's not great, of course, because it means you simply can't start a page or login using 10.63. But you can at least progress in some way. However, this one lightbox is persistent for some reason — I suppose because it requires input. This means you can't even click the box which says "don't show me this again". That, in turn, means you never get to the Layout Builder at all, which — you guessed it — indicates that, fundamentally, Layout Builder is incompatible with Opera 10.63. Course, since all Macs come with Safari by default, the workaround would probably be to dismiss the lightbox in Safari so that it doesn't recur in Opera. But that's cheating. :)

I've already filed an extensive bug report, but I thought the (PPC Mac using) community might benefit from a more public notice.