Fildem not working on Ubuntu 20.04

[namnh198]

I try to run command fildem on terminal. But it shows error:

Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/home/namnh198/.local/lib/python3.8/site-packages/fildem/keybinder.py", line 30, in main
    run_keybinder(default_hud_menu)
  File "/home/namnh198/.local/lib/python3.8/site-packages/fildem/keybinder.py", line 19, in run_keybinder
    dbus_menu = DbusMenu()
  File "/home/namnh198/.local/lib/python3.8/site-packages/fildem/utils/menu.py", line 27, in __init__
    self._init_window()
  File "/home/namnh198/.local/lib/python3.8/site-packages/fildem/utils/menu.py", line 34, in _init_window
    self._update()
  File "/home/namnh198/.local/lib/python3.8/site-packages/fildem/utils/menu.py", line 122, in _update
    self._update_menus()
  File "/home/namnh198/.local/lib/python3.8/site-packages/fildem/utils/menu.py", line 114, in _update_menus
    self._menu_model._update_menus()
  File "/home/namnh198/.local/lib/python3.8/site-packages/fildem/menu_model/menu_model.py", line 318, in _update_menus
    self.gtkmenu.get_results()
  File "/home/namnh198/.local/lib/python3.8/site-packages/fildem/menu_model/menu_model.py", line 70, in get_results
    self.collect_entries(treelib_parent='Root')
  File "/home/namnh198/.local/lib/python3.8/site-packages/fildem/menu_model/menu_model.py", line 93, in collect_entries
    self.collect_entries(menu[':submenu'], menu_path, menu_item.action)
  File "/home/namnh198/.local/lib/python3.8/site-packages/fildem/menu_model/menu_model.py", line 98, in collect_entries
    self.collect_entries(menu[':section'], labels, treelib_parent)
  File "/home/namnh198/.local/lib/python3.8/site-packages/fildem/menu_model/menu_model.py", line 90, in collect_entries
    self.tree.create_node(menu_item.label, menu_item.action, treelib_parent, data=menu_item)
  File "/home/namnh198/.local/lib/python3.8/site-packages/fildem/treelib/tree.py", line 345, in create_node
    self.add_node(node, parent)
  File "/home/namnh198/.local/lib/python3.8/site-packages/fildem/treelib/tree.py", line 268, in add_node
    raise DuplicatedNodeIdError("Can't create node "
fildem.treelib.exceptions.DuplicatedNodeIdError: Can't create node with ID ''

Information:
OS: Ubuntu 20.04.3
Gnome version: 3.36