Left mouse button doesn't release with QT terminal

Report taken from http://sourceforge.net/p/gnuplot/bugs/1367/

If I could find the commit I would have attached the patch, but unfortunately I couldn't.

--------------------------------------------------------------------------
When using the QT terminal, it is not possible to stop rotating the plot (created with splot), after using the left mouse button.

With the X11 terminal everything works correctly, i.e. the plot can be rotated only while the left mouse button is pressed. However, with the QT terminal, it is as if the left mouse button is never released, and no other mouse operations can then be done (e.g. zoom). And worse, it is not possible to reach the "Save"-menu without rotating the plot...

ProblemType: Bug
DistroRelease: Ubuntu 14.10
Package: gnuplot-qt 4.6.5-10
ProcVersionSignature: Ubuntu 3.16.0-23.31-generic 3.16.4
Uname: Linux 3.16.0-23-generic x86_64
ApportVersion: 2.14.7-0ubuntu8
Architecture: amd64
CurrentDesktop: KDE
Date: Thu Oct 23 17:48:38 2014
InstallationDate: Installed on 2014-07-11 (103 days ago)
InstallationMedia: Kubuntu 14.10 "Utopic Unicorn" - Alpha amd64 (20140710)
SourcePackage: gnuplot
UpgradeStatus: No upgrade log present (probably fresh install)