[shades] Traceback

[GreenLunar]

On enabling:

Traceback (most recent call last):
  File "/home/HOSTNAME/.local/share/liferea/plugins/shades/shades.py", line 263, in do_activate
    current_views = self.current_webviews
  File "/home/HOSTNAME/.local/share/liferea/plugins/shades/shades.py", line 242, in current_webviews
    html_in_tabs = [x.htmlview for x in browser_tabs.props.tab_info_list]
TypeError: 'NoneType' object is not iterable

On disabling:

Traceback (most recent call last):
  File "/home/HOSTNAME/.local/share/liferea/plugins/shades/shades.py", line 274, in do_deactivate
    current_views = self.current_webviews
  File "/home/HOSTNAME/.local/share/liferea/plugins/shades/shades.py", line 242, in current_webviews
    html_in_tabs = [x.htmlview for x in browser_tabs.props.tab_info_list]
TypeError: 'NoneType' object is not iterable

On clicking on Preferences button:

(liferea:3745): libpeas-CRITICAL **: show_configure_cb: assertion `GTK_IS_WIDGET (conf_widget)' failed