/usr/share/app-install/desktop/mtpaint:mtpaint.desktop is in app-install-data 14.04.0.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 | [Desktop Entry]
X-AppInstall-Package=mtpaint
X-AppInstall-Popcon=397
X-AppInstall-Section=universe
Version=1.0
Name=mtPaint graphic editor
GenericName=Painting program
Comment=painting program to create pixel art and manipulate digital photos
Type=Application
Exec=mtpaint
Icon=mtpaint
Categories=Graphics;RasterGraphics;
X-Ubuntu-Gettext-Domain=app-install-data
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