/usr/share/app-install/desktop/gxkb:gxkb.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 15 16 | [Desktop Entry]
X-AppInstall-Package=gxkb
X-AppInstall-Popcon=0
X-AppInstall-Section=universe
Name=Gxkb
Comment=Keyboard switcher
GenericName=Keyboard switcher
Exec=gxkb
Icon=_usr_share_pixmaps_gxkb
Terminal=false
Type=Application
Categories=Application;Utility;
Keywords=keyboard;switcher;language;
X-Ubuntu-Gettext-Domain=app-install-data
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