I've experienced this problem for a long time now (at least one year!), but usually I'm not able to reproduce it. The steps are more or less as follows:
- Open the following page in a new (anonymous) window, using Google Chrome (tried with version 28.0.1500.71):
- Click in the search box
- Type "Special:Prefix" and wait for the list of suggestions
- Press the down arrow to select the first suggestion, which is "Special:PrefixIndex". This will change the content of the search field to this title.
- Type "/A" after to get "Special:PrefixIndex/A" and press ENTER
At this point, I'm taken to the page
instead of what I want: