Uncaught TypeError: 'QVariant' object is not subscriptable

[UrbanPlan-LDB]

Impossibile caricare il plugin 'selectThemes' a causa di un errore chiamando il metodo classFactory()
Steps to reproduce

1. First
2. Second
3. Third

Traceback (most recent call last):
  File "G:\OSGeo4W/apps/qgis/./python\qgis\utils.py", line 423, in _startPlugin
    plugins[packageName] = package.classFactory(iface)
  File "C:\Users/Lucio De Benedictis/AppData/Roaming/QGIS/QGIS3\profiles\Lucio_02_23/python/plugins\selectThemes\__init__.py", line 37, in classFactory
    return selectThemes(iface)
  File "C:\Users/Lucio De Benedictis/AppData/Roaming/QGIS/QGIS3\profiles\Lucio_02_23/python/plugins\selectThemes\selectThemes.py", line 52, in __init__
    self.locale = QSettings().value('locale/userLocale')[0:2]
TypeError: 'QVariant' object is not subscriptable

selectThemes 3.0.1, QGIS 3.30.0-'s-Hertogenbosch on Windows 10

[AlisterH]

The offending line of code should be replaced by this:

self.locale = QgsSettings().value('locale/userLocale', QLocale().name())[0:2]

[AlisterH]

Which itself probably requires:

from qgis.PyQt.QtCore import QLocale
from qgis.core import QgsSettings