Am 07.05.2015 um 15:11 schrieb Bartosz Dziewoński:
The "page you last visited" is probably actually a link to the 'returnto' page. The link was changed to an automatic redirect in MediaWiki 1.24 (https://gerrit.wikimedia.org/r/#/c/148144/ / d0439af89f6b254cea09b3773ab139f04f81a97d).
Indeed it is. The particular wiki in question is currently on 1.22.15 (shame on me but there are reasons) and I did also try to make it work in 1.23.8 so I had not chance.
Thank you so much for your information on this which helps a lot. So I guess it's time to upgrade sooner than later anyway.
Cheers Karsten