/etc/bash_completion.d/lxctl_restart is in lxctl 0.3.1+debian-4.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | LXCTL_PLUGINS="$LXCTL_PLUGINS restart"
LXCTL_PLUGIN_restart=""
LXCTL_PLUGIN_USE_VMNAME_restart="yes"
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