/usr/share/ubuntustudio/applications/ is in ubuntustudio-default-settings 0.54.
This file is owned by root:root, with mode 0o755.
..
/usr/share/ubuntustudio/applications/Thunar-bulk-rename.desktop
/usr/share/ubuntustudio/applications/Thunar.desktop
/usr/share/ubuntustudio/applications/debian-uxterm.desktop
/usr/share/ubuntustudio/applications/debian-xterm.desktop
/usr/share/ubuntustudio/applications/defaults.list
/usr/share/ubuntustudio/applications/hdspmixer.desktop
/usr/share/ubuntustudio/applications/hexter.desktop
/usr/share/ubuntustudio/applications/us-gcm-calibrate.desktop
/usr/share/ubuntustudio/applications/us-gcm-picker.desktop
/usr/share/ubuntustudio/applications/us-gcm-viewer.desktop
/usr/share/ubuntustudio/applications/xfce4-terminal.desktop