Anki 2.1.20beta6 add note dialog error

[khonkhortisan]

Error 
An error occurred. Please start Anki while holding down the shift key, which will temporarily disable the add-ons you have installed. 
If the issue only occurs when add-ons are enabled, please use the Tools>Add-ons menu item to disable some add-ons and restart Anki, repeating until you discover the add-on that is causing the problem. 
When you've discovered the add-on that is causing the problem, please report the issue on the add-ons section of our support site. 
Debug info:
Anki 2.1.20 (23f13a31) Python 3.8.0 Qt 5.14.0 PyQt 5.13.2
Platform: Windows 10
Flags: frz=True ao=True sv=2

Caught exception:
Traceback (most recent call last):
  File "aqt\main.py", line 967, in onAddCard
  File "aqt\__init__.py", line 92, in open
  File "<C:\Program Files\Anki\decorator.pyc:decorator-gen-132>", line 2, in __init__
  File "lib\site-packages\anki\hooks.py", line 506, in decorator_wrapper
  File "lib\site-packages\anki\hooks.py", line 498, in repl
  File "C:\Users\Khonkhortisan\AppData\Roaming\Anki2\addons21\1914733489\internals.py", line 218, in raw_new
    return wrapper(cls.instance, *args, **kwargs)
  File "C:\Users\Khonkhortisan\AppData\Roaming\Anki2\addons21\1914733489\stylers.py", line 630, in init
    add_cards.form.line.setStyleSheet('#' + from_utf8('line') + '{border: 0px solid #333}')
AttributeError: 'Ui_Dialog' object has no attribute 'line'

[info] https://anki.tenderapp.com/discussions/beta-testing/1708-anki-2120-beta