Use of '^' character to redirect stderr has been deprecated starting
Fish version 3.1. It now produces an error. Stderr should be redirected
with '2>' like on SH shells. Hopefully '2>' redirection is also
supported on old Fish versions (all version 2 support it).
This update was performed on modulecmd.tcl with 711c901 commit, but fish
initialization script was forgotten at that time.