Comment # 1 on bug 942810 from Wolfgang Bauer

(In reply to Jon Buckingham from comment #0)
> That's actually kdelibs4's fault. It contains a debug statement in ktextedit
> that outputs every pressed key to stderr.
> The same happens when you rename a file in dolphin e.g.
> 
> It has been fixed recently with the following commit:
> https://quickgit.kde.org/?p=kdelibs....2e5d91c7855609

This is fixed in kdelibs 4.14.11 (it contains the mentioned commit), which has
been released last week as part of the KDE Applications 15.08.0 release.

I would suggest to just release that version as update for 13.2.

Btw, this is also an issue in latest Tumbleweed. kdelibs4 hasn't been updated
to 4.14.11 yet in KDE:Distro:Factory either.