/usr/share/mimelnk/application/x-treeline.desktop is in treeline 1.4.1-1.
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]
Encoding=UTF-8
Type=TreeLineType
MimeType=application/x-treeline
Comment=TreeLine Data
Comment[es]=Datos de TreeLine
Icon=treeline
Patterns=*.trl;
|