I'm wondering why this hook never works:
(add-hook 'gnus-group-prepared-hook 'gnus-group-list-all-groups)
Description of the hook:
is called as the very last thing after the group buffer has been generated. It may be used to move point around, for instance.
I've also tried
gnus-group-mode-hook (specified function is called, but no effect) and
gnus-group-prepare-hook (never called).
Expected behavior: when I start Gnus via M-x gnus, it should list all groups immediately.