… it didn't work

The old uses syntax unavailable in Safari, which is not a problem for
me, but it is not working (for unknown reason) in the browser built-in
to Android 6.

This is an attempt to fix that.

constraints.txt

@@ -2,3 +2,6 @@ Django>=3.1
 # Django-autocomplete-light does not play nicely with Django 4.0, so limit that for now.
 Django<4
 django-sendmail-backend==0.1.2
+
+# Old django-autocomplete-light does not support Safari and maybe Android built-in browser…
+django-autocomplete-light>=3.9.0rc1