Opera 12.17 vs thread attachments

[#1]

Recently if someone attaches anything to a thread, if clicking it to view it the attachment is no longer forced to open in a new tab, but replaces the thread its from.  A minor annoyance but it is a recent change, as up until now attachments have always opened in a  new tab.

[#2]

I use Opera 12.17 and have not seen this problem.
Can you post a link to an example?

[#3]

Gus,
I'm not convinced that this is a change.  I have seen on the same platform (both IE and Safari) some attachments open in the same window / tab and also launch a new window.  I'm guessing it must be down to how I'm clicking them, but have yet to discern a pattern.  Now you've mentioned it. I'll try to be more observant!
Kevin