/usr/share/applications/mono-runtime-common.desktop is in mono-runtime-common 4.2.1.102+dfsg2-7ubuntu4.
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=Mono Runtime
Exec=mono
Terminal=false
Type=Application
Icon=mono-runtime-common
MimeType=application/x-ms-dos-executable;
NoDisplay=true
|