/etc/apparmor.d/abstractions/fcitx-strict is in apparmor 2.12-4ubuntu5.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 | # vim:syntax=apparmor
# ------------------------------------------------------------------
#
#    Copyright (C) 2016 Canonical Ltd.
#
#    This program is free software; you can redistribute it and/or
#    modify it under the terms of version 2 of the GNU General Public
#    License published by the Free Software Foundation.
#
# ------------------------------------------------------------------
  #include <abstractions/dbus-session-strict>
  dbus send
      bus=fcitx
      path=/org/freedesktop/DBus
      interface=org.freedesktop.DBus
      member={Hello,AddMatch,RemoveMatch,GetNameOwner,NameHasOwner,StartServiceByName}
      peer=(name=org.freedesktop.DBus),
  owner @{HOME}/.config/fcitx/dbus/* r,
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