/usr/share/applications/inputmethods/matchbox-keyboard.desktop is in matchbox-keyboard 0.1+svn20080916-11.
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 | [Desktop Entry]
Name=Keyboard
Comment=Virtual Keyboard
Exec=matchbox-keyboard
Type=Application
Icon=matchbox-keyboard.png
Categories=Panel;Utility;MB
X-MB-INPUT-MECHANSIM=True
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