[
{
  type: upgrade
  maximum_version: "0.4.0"
  message: <<EOM
river 0.4.0+ is a breaking release and splits the compositor and window
manager into separate processes. The river compositor no longer includes
a window manager, instead users can choose any window manager implementing
the protocol.

If you are happy with how river 0.3 works and do not want to change your
setup, please consider switching to x11-wm/river-classic, a maintained
fork of river 0.3.

For more info, see https://isaacfreund.com/blog/river-window-management/

EOM
}
]