always use FilteredSelectMultiple for many-to-many fields

passbook/hibp_policy/forms.py

@@ -1,6 +1,8 @@
 """passbook HaveIBeenPwned Policy forms"""
 
 from django import forms
+from django.contrib.admin.widgets import FilteredSelectMultiple
+from django.utils.translation import gettext as _
 
 from passbook.core.forms.policies import GENERAL_FIELDS
 from passbook.hibp_policy.models import HaveIBeenPwendPolicy
@@ -16,4 +18,5 @@ class HaveIBeenPwnedPolicyForm(forms.ModelForm):
         widgets = {
             'name': forms.TextInput(),
             'order': forms.NumberInput(),
+            'policies': FilteredSelectMultiple(_('policies'), False)
         }