/usr/share/app-install/desktop/mnemosyne:mnemosyne.desktop is in app-install-data 15.10.
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 | [Desktop Entry]
X-AppInstall-Package=mnemosyne
X-AppInstall-Popcon=27
X-AppInstall-Section=universe
Name=Mnemosyne
Comment=A flash card program to make your review process more efficient
Exec=mnemosyne %f
Icon=mnemosyne
Categories=Education
Terminal=false
Type=Application
X-Ubuntu-Gettext-Domain=app-install-data
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