🐛 forms: fix availability of disabled types on m2m fields (refs #6266)

This bug only occurs when many types are selected.

2 files changed, 4 insertions, 2 deletions

diff --git a/ishtar_common/forms.py b/ishtar_common/forms.py
index 468fb32f1..20849c400 100644
--- a/ishtar_common/forms.py
+++ b/ishtar_common/forms.py
@@ -44,6 +44,7 @@ from django.utils.translation import ugettext_lazy as _
 from bootstrap_datepicker.widgets import DatePicker, DATE_FORMAT, DateField
 from ishtar_common import models
 from ishtar_common import widgets
+
 from ishtar_common.utils import MultiValueDict
 
 
@@ -1194,8 +1195,9 @@ class ManageOldType(IshtarForm):
     def _init_type(self, field):
         if field.key not in self.fields:
             return
+        initial = self.init_data.getlist(field.key)
         self.fields[field.key].choices = field.get_choices(
-            initial=self.init_data.get(field.key)
+            initial=initial
         )
         self.fields[field.key].help_text = field.get_help()
 
diff --git a/ishtar_common/models_common.py b/ishtar_common/models_common.py
index d932abf66..9f5be1e36 100644
--- a/ishtar_common/models_common.py
+++ b/ishtar_common/models_common.py
@@ -349,7 +349,7 @@ class GeneralType(Cached, models.Model):
         new_vals = []
         if not initial:
             return []
-        if type(initial) not in (list, tuple):
+        if not isinstance(initial, (list, tuple)):
             initial = [initial]
         for value in initial:
             try: