/usr/share/xfce4/helpers/ is in libexo-helpers 0.12.0-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/xfce4/helpers/Thunar.desktop
/usr/share/xfce4/helpers/aterm.desktop
/usr/share/xfce4/helpers/balsa.desktop
/usr/share/xfce4/helpers/brave.desktop
/usr/share/xfce4/helpers/caja.desktop
/usr/share/xfce4/helpers/chromium.desktop
/usr/share/xfce4/helpers/debian-sensible-browser.desktop
/usr/share/xfce4/helpers/debian-x-terminal-emulator.desktop
/usr/share/xfce4/helpers/dillo.desktop
/usr/share/xfce4/helpers/encompass.desktop
/usr/share/xfce4/helpers/epiphany.desktop
/usr/share/xfce4/helpers/eterm.desktop
/usr/share/xfce4/helpers/evolution.desktop
/usr/share/xfce4/helpers/firefox.desktop
/usr/share/xfce4/helpers/galeon.desktop
/usr/share/xfce4/helpers/geary.desktop
/usr/share/xfce4/helpers/gnome-terminal.desktop
/usr/share/xfce4/helpers/google-chrome.desktop
/usr/share/xfce4/helpers/icecat.desktop
/usr/share/xfce4/helpers/icedove.desktop
/usr/share/xfce4/helpers/iceweasel.desktop
/usr/share/xfce4/helpers/jumanji.desktop
/usr/share/xfce4/helpers/kmail.desktop
/usr/share/xfce4/helpers/konqueror.desktop
/usr/share/xfce4/helpers/links.desktop
/usr/share/xfce4/helpers/lynx.desktop
/usr/share/xfce4/helpers/midori.desktop
/usr/share/xfce4/helpers/mozilla-browser.desktop
/usr/share/xfce4/helpers/mozilla-mailer.desktop
/usr/share/xfce4/helpers/mutt.desktop
/usr/share/xfce4/helpers/muttng.desktop
/usr/share/xfce4/helpers/nautilus.desktop
/usr/share/xfce4/helpers/netscape-navigator.desktop
/usr/share/xfce4/helpers/nxterm.desktop
/usr/share/xfce4/helpers/opera-browser.desktop
/usr/share/xfce4/helpers/pcmanfm.desktop
/usr/share/xfce4/helpers/qterminal.desktop
/usr/share/xfce4/helpers/qtfm.desktop
/usr/share/xfce4/helpers/qupzilla.desktop
/usr/share/xfce4/helpers/rodent.desktop
/usr/share/xfce4/helpers/rox-filer.desktop
/usr/share/xfce4/helpers/sakura.desktop
/usr/share/xfce4/helpers/surf.desktop
/usr/share/xfce4/helpers/sylpheed-claws.desktop
/usr/share/xfce4/helpers/sylpheed.desktop
/usr/share/xfce4/helpers/terminator.desktop
/usr/share/xfce4/helpers/thunderbird.desktop
/usr/share/xfce4/helpers/urxvt.desktop
/usr/share/xfce4/helpers/vimprobable2.desktop
/usr/share/xfce4/helpers/w3m.desktop
/usr/share/xfce4/helpers/xfce4-terminal.desktop
/usr/share/xfce4/helpers/xfe.desktop
/usr/share/xfce4/helpers/xterm.desktop