UnboundLocalError: local variable 'transport' referenced before assignment when sending a file using gajim-remote

Versions

• OS: Ubuntu 20.10
• GTK Version: 3.24.23
• PyGObject Version: 3.38.0
• GLib Version : 2.66.0
• python-nbxmpp Version: 1.0.1
• Gajim Version: 1.2.1

Traceback

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/gajim/remote_control.py", line 99, in on_method_call
    result = getattr(self, method_name)(*args)
  File "/usr/lib/python3/dist-packages/gajim/remote_control.py", line 493, in send_file
    app.interface.instances['file_transfers'].send_file(
  File "/usr/lib/python3/dist-packages/gajim/gtk/filetransfer.py", line 373, in send_file
    app.connections[account].get_module('Jingle').start_file_transfer(
  File "/usr/lib/python3/dist-packages/gajim/common/modules/jingle.py", line 213, in start_file_transfer
    transport=transport,
UnboundLocalError: local variable 'transport' referenced before assignment

Steps to reproduce the problem

I tried to send a file to one of my contacts using gajim-remote and it crashed:

$ gajim-remote send_file Pictures/Screenshot\ at\ 2021-05-06\ 12-26-31.png user@example.com
No translations found
Dirs searched: [PosixPath('/usr/share/mate'), PosixPath('/usr/local/share'), PosixPath('/usr/share'), PosixPath('/var/lib/snapd/desktop')]
$ echo $?
1