dovecot - Sep 2018 - dovecot_deleted_to_trash no longer compiles with dovecot 2.3.2.1

I have just upgraded to the latest version of dovecot (Gentoo amd64).
When I try to compile the dovecot_deleted_to_trash plugin it won't
compile.  Is this plugin going to be updated (from
https://github.com/lexbrugman/dovecot_deleted_to_trash - same error
from https://github.com/NethServer/dovecot-deleted-to-trash)?

 # make
cc    \
      -fPIC -shared -Wall \
      -I/usr/include/dovecot \
      -I/usr/include/dovecot/src \
      -I/usr/include/dovecot/src/lib \
      -I/usr/include/dovecot/src/lib-storage \
      -I/usr/include/dovecot/src/lib-mail \
      -I/usr/include/dovecot/src/lib-imap \
      -I/usr/include/dovecot/src/lib-index \
      -DHAVE_CONFIG_H \
      src/deleted-to-trash-plugin.c -o lib_deleted_to_trash_plugin.so
src/deleted-to-trash-plugin.c: In function ?copy_deleted_mail_to_trash?:
src/deleted-to-trash-plugin.c:117:16: error: too few arguments to
function ?mail
                 box_transaction_begin?
   dest_trans = mailbox_transaction_begin(trash_box,
MAILBOX_TRANSACTION_FLAG_EX
                              TERNAL);
                ^~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/dovecot/mail-storage-private.h:7:0,
                 from src/deleted-to-trash-plugin.h:5,
                 from src/deleted-to-trash-plugin.c:4:
/usr/include/dovecot/mail-storage.h:656:1: note: declared here
 mailbox_transaction_begin(struct mailbox *box,
 ^~~~~~~~~~~~~~~~~~~~~~~~~
make: *** [Makefile:32: lib_deleted_to_trash_plugin.so] Error 1

Some further info:

# dovecot -n
# 2.3.2.1 (0719df592): /etc/dovecot/dovecot.conf
# OS: Linux 4.14.8-gentoo-r1 x86_64 Gentoo Base System release 2.4.1
# Hostname: basement-vm.schmidli.com.au
doveconf: Warning: please set ssl_dh=</etc/dovecot/dh.pem
doveconf: Warning: You can generate it with: dd
if=/var/lib/dovecot/ssl-parameters.dat bs=1 skip=88 | openssl dhparam
-inform der > /etc/dovecot/dh.pem
dict {
  expire = db:/var/lib/dovecot/expire.db
}
disable_plaintext_auth = no
listen = *
mail_location = maildir:~/.maildir
mail_plugins = deleted_to_trash mailbox_alias
namespace inbox {
  inbox = yes
  location   mailbox Drafts {
    special_use = \Drafts
  }
  mailbox Junk {
    special_use = \Junk
  }
  mailbox Sent {
    special_use = \Sent
  }
  mailbox "Sent Messages" {
    special_use = \Sent
  }
  mailbox Trash {
    special_use = \Trash
  }
  prefix }
passdb {
  args = *
  driver = pam
}
plugin {
  deleted_to_trash_folder = Trash
  expire = Trash 7 Spam 30
  expire_dict = proxy::expire