Blacklist module not open in settings after activated

[Usernm0]

Build: Develop-7

Steps to reproduce:

1. Start chat.
2. Open settings -> Messaging Modules.
3. Activate blacklist module.
4. Save settings and close chat.
5. Start chat.
6. Open settings -> Messaging Modules -> Blacklist

Expected: Blacklist module settings opens.

Bug: Blacklist module sttings not opens. Console error:

Traceback (most recent call last):
  File "src\modules\gui.py", line 306, in on_tree_ctrl_changed
  File "src\modules\gui.py", line 495, in fill_page_with_content
  File "src\modules\gui.py", line 524, in create_page
  File "src\modules\gui.py", line 565, in create_page_items
  File "src\modules\interface\elements.py", line 165, in create_list
  File "src\modules\interface\types.py", line 193, in __iter__
AttributeError: 'NoneType' object has no attribute '__iter__'

[DeForce]

Should be fixed