Now, if you also want deskopen to pass through any command-line parameters, you can instead use this slightly-modified version: #!/bin/sh desktop_file=$1 shift `grep '^Exec' "${desktop_file}" | sed 's/^Exec=//' | sed 's/%.//'` "$@" &

A solution is almost indicated in the question: hinder xdg-open from choosing exo-open. A brute-force approach is to copy /usr/bin/xdg-open to /usr/local/bin (/usr/local/bin is earlier in PATH unless PATH has been modified) and to patch it to use open_generic instead of exo_open (unlike the XFCE4-specific exo-open, open_generic does honor xdg mime types)