Plus! GUI returns KeyError: 'glyphs' when attempting to load a theme

Hi! Themes aren't working for some reason.

I get the error

```WARNING: The convert command is deprecated in IMv7, use "magick" instead of "convert" or "magick convert"

[MakePreview] Fonts... [MakePreview] Generating Preview Image
[MakePreview] Metrics... OK
Traceback (most recent call last):
File "/home/admin/Scrivania/.Chicago95/Plus/./PlusGUI.py", line 872, in open_file
self.preview_image = MakePreview(self.theme)
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/admin/Scrivania/.Chicago95/Plus/./PlusGUI.py", line 110, in __init__
self.set_fonts()
File "/home/admin/Scrivania/.Chicago95/Plus/./PlusGUI.py", line 171, in set_fonts
self.lfMessageFont = self.get_font(self.msgfont)
^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/admin/Scrivania/.Chicago95/Plus/./PlusGUI.py", line 384, in get_font
return self.get_font("Noto-Sans-Regular")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/admin/Scrivania/.Chicago95/Plus/./PlusGUI.py", line 365, in get_font
return installed_fonts[fontname]['glyphs']
~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^
KeyError: 'glyphs'```