Generic view does not support the "HEAD" method.

[nikolaysm]

django-haystack/haystack/generic_views.py

Line 61 in c506696

if self.request.method == 'GET':

As Django's default handling of the HEAD method as GET, it would be beneficial to include data in the form even when a HEAD method is requested to align with Django's expected behavior.

To support HEAD method we can do:
if self.request.method in ['GET', 'HEAD']: