This appears to be a Google Chrome problem. You can read the bug report here: https://code.google.com/p/chromium/issues/detail?id=236835, but the basic idea is that there is a problem with opening urls that include a '#' in new tabs using the normal shortcut keys.

Apparently it was an issue in 27 too, but less visible (only occurs if you try to open the same link twice in a new tab).

The good news is that we plan to remove the #'s in the fairly near future, so it should return to normal functionality soon. For now, unfortunately, the only workaround appears to be to using right click, "Open Link in New Tab" or updating to a non stable version like 29 or Canary.

Thanks for the report!

Hi Christian! Thanks for reporting this. We were able to replicate it. We'll get this fixed soon.

I just started seeing a very similar issue in Firefox. I usually hold ctrl while clicking links to open them in a new tab, and this stopped working on Duolingo either yesterday or today. Same effects for me: opens in same tab, works fine everywhere else.

I am using Chrome and it is working fine. I just clicked someone's name and also a tab at the top. It opened both in a new tab. But I don't know if this Chrome has been updated which may be why it is still works.

Same problem with Chrome + Mac OS, I open pages in new tab with [command] + [L-click] but lately it does not work, it opens the link in the same tab.