Open up qtconsole and use the keyboard to type select-all, kill (C-A C-k). This gives you an empty window where you can type but enter/return do not work.
Clearing the screen (C-l) does fix it.
I did have a quick look.
Issues is in console_widget.py around L1050 when killing cursor with the kill ring.
Is there a particular reason to a different implementation for cutting normal (Ctrl+x) versus cutting kill ring (Ctrl+k) except for the rotation part ? Can't the two just call self.cut() (well implemented) and depending on wether kor x is pressed append (or not) to the ring ?
@Carreau, I don't really think so. We don't implement a full-blown emacs-style kill ring with multiple levels, so I don't think there needs to be a difference. Perhaps @epatters has some insights here?
BUG: Ctrl+K and Ctrl+U shortcuts unsafe in Qt console.
Actually, we do implement a kill ring with multiple recall ala Emacs. Trying killing several things, then doing C-y followed by M-y.
In any case, this is fixed.