CheckboxSelectMultiple widget doesn't work with TextChoices enabled CharFields

[Remy]

# forms.py

class MovieForm(forms.ModelForm):

    class Meta:
        model = Movie
        fields = [
            'genres',
        ]
        widgets = {
            'genres': forms.CheckboxSelectMultiple
        }

# models.py

class Movie(models.Model):
    class Genre(models.TextChoices):
        SCIFI = 'S', 'Science Fiction'
        ACTION = 'A', 'Action'

    genres = models.CharField(max_length=1, choices=Genre.choices)

# template

{{ form.genres.errors }}

Select one checkbox for example, then post the form. On form.save(), the following error is returned to the template:

"Select a valid choice. ['S'] is not one of the available choices."

[Mariusz Felisiak]

It's not related with TextChoices, it will not work also with choices=[('S', 'Science Fiction'), ('A', 'Action')] because CharField cannot handle multiple values. Please use one of support channels.