You may have noticed that, since the forum upgrade, clicking on a link behaves differently.
Previously, if you clicked on a link (like the link some people have in their signature), the new page would appear in a new tab in your browser, if your browser supported tabs. Possibly, it would appear in a new window, it depends a bit on the browser brand and version.
Since the upgrade, if you click on a link, the new page will replace the current one, and not create a new tab or window. This could be very annoying if you are used to the old behaviour.
So why is this happening ?
It's not our mistake or decision, but a feature of PhpBB version 3. The designers of PhpBB wanted a better conformance with HTML standards, which dictate that by default, a click on a link shall replace the current page. If the user wants it differently, they have the choice to use
Code:
ctrl-click ---> Link opens in a new tab
shift-click ---> Link opens in new window
Try it out, it works - at least on IE and Firefox, I did not try other browsers.
It seems to be possible to change it back to the old behaviour by hacking the php code, but I'm not in favour of that.
First, it's work. I don't like work.

Second, it will be better to get used to use ctrl-click or shift-click as needed.
The advantage of replacing the current page is that you can simply do backspace, instead of cluttering up your desktop with windows and tabs you need to explicitly close.