There are some adapters on the allauth configuration. For example this one:
ACCOUNT_ADAPTER (="allauth.account.adapter.DefaultAccountAdapter") Specifies the adapter class to use, allowing you to alter certain default behaviour.
Override the default one and set your own on the settings:
settings.py
ACCOUNT_ADAPTER = 'MyAdapter'
somewhere.py
class MyAdapter(DefaultAccountAdapter):
def get_login_redirect_url(self, request):
return request.GET['next']
Check the default behavior on: https://github.com/pennersr/django-allauth/blob/master/allauth/account/adapter.py