/usr/share/applications/mono-runtime-terminal.desktop is in mono-runtime-common 4.6.2.7+dfsg-1ubuntu1.
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 (Terminal)
Exec=mono
Terminal=true
Type=Application
Icon=mono-runtime-common
MimeType=application/x-ms-dos-executable;
NoDisplay=true
|