Binary package hint: kdiff3
There is an offset from where the cursor actually is and where any change actually happens (about 4 places to the left from the cursor).
In addition, kdiff3 gives these messages on launch:
QInotifyFileSystemWatcherEngine::addPaths: inotify_add_watch failed: No such file or directory
QFileSystemWatcher: failed to add paths: /home/user/.config/ibus/bus
Bus::open: Can not get ibus-daemon's address.
IBusInputContext::createInputContext: no connection to ibus-daemon
kdiff3(14836) KXMLGUIClient::setXMLFile: cannot find .rc file "kdiff3_part.rc" for component "kdiff3part"
Calling appendChild() on a null node does nothing.
ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: kdiff3 0.9.95-4ubuntu1
ProcVersionSignature: Ubuntu 2.6.32-20.30-generic 2.6.32.11+drm33.2
Uname: Linux 2.6.32-20-generic x86_64
NonfreeKernelModules: wl
Architecture: amd64
Date: Thu Apr 15 18:35:08 2010
InstallationMedia: Kubuntu 10.04 "Lucid Lynx" - Beta amd64 (20100406.1)
ProcEnviron:
LANGUAGE=
PATH=(custom, username)
LANG=en_IN
SHELL=/bin/zsh
SourcePackage: kdiff3
I don't seem to have the offset problem but I do have those IBus and KXMLGUIClient messages emitted by kdiff3