/usr/lib/GNUstep/Applications/iceweasel.app is in gworkspace-apps-wrappers 0.9.3-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/GNUstep/Applications/../../../share/GNUstep/iceweasel.app
/usr/lib/GNUstep/Applications/../../../share/GNUstep/iceweasel.app