Icon in launcher reverts to the "?"

[Alan Lord]

I installed Gcolor2 yesterday from the Software Centre and a representative icon appeared in my launcher.

The following morning (after a PC shutdown and restart overnight) the icon is not there any more and it is replaced by the grey box with a "?" in it.

Clicking that launcher icon still starts gcolor2 but the icon remains the default grey "?" one.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: gcolor2 0.4-2ubuntu2
ProcVersionSignature: Ubuntu 3.2.0-25.40-generic 3.2.18
Uname: Linux 3.2.0-25-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.0.1-0ubuntu8
Architecture: amd64
Date: Thu Jun 21 08:07:23 2012
ExecutablePath: /usr/bin/gcolor2
ProcEnviron:
 LANGUAGE=en_GB:en
 PATH=(custom, user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: gcolor2
UpgradeStatus: No upgrade log present (probably fresh install)
XsessionErrors:
 (gnome-settings-daemon:2571): color-plugin-WARNING **: failed to get edid: unable to get EDID for output
 (gnome-settings-daemon:2571): color-plugin-WARNING **: unable to get EDID for xrandr-default: unable to get EDID for output
 (gnome-settings-daemon:2571): color-plugin-WARNING **: failed to reset xrandr-default gamma tables: gamma size is zero
 (compiz:2588): GConf-CRITICAL **: gconf_client_add_dir: assertion `gconf_valid_key (dirname, NULL)' failed