[1.11.x] Fixed #27993 -- Fixed model form default fallback for SelectMultiple.

Backport of 7d1e23775344cc3dead03bd4af45f4fdf134b819 from master

1 files changed, 7 insertions, 5 deletions

diff --git a/docs/topics/forms/modelforms.txt b/docs/topics/forms/modelforms.txt
index bc0c124014..c0f032f3e3 100644
--- a/docs/topics/forms/modelforms.txt
+++ b/docs/topics/forms/modelforms.txt
@@ -337,12 +337,14 @@ doesn't validate -- i.e., if ``form.errors`` evaluates to ``True``.
 If an optional field doesn't appear in the form's data, the resulting model
 instance uses the model field :attr:`~django.db.models.Field.default`, if
 there is one, for that field. This behavior doesn't apply to fields that use
-:class:`~django.forms.CheckboxInput` and
-:class:`~django.forms.CheckboxSelectMultiple` (or any custom widget whose
+:class:`~django.forms.CheckboxInput`,
+:class:`~django.forms.CheckboxSelectMultiple`, or
+:class:`~django.forms.SelectMultiple` (or any custom widget whose
 :meth:`~django.forms.Widget.value_omitted_from_data` method always returns
-``False``) since an unchecked checkbox doesn't appear in the data of an HTML
-form submission. Use a custom form field or widget if you're designing an API
-and want the default fallback for a :class:`~django.db.models.BooleanField`.
+``False``) since an unchecked checkbox and unselected ``<select multiple>``
+don't appear in the data of an HTML form submission. Use a custom form field or
+widget if you're designing an API and want the default fallback behavior for a
+field that uses one of these widgets.
 
 .. versionchanged:: 1.10.1