With the new version 4.2 of Django, some templates (in my case: stacked-django-4.2.html but this should also apply to tabular-django-4.2.html) are missing. The templates for 4.1 can be used and should be included in a newer version of the plugin. As a hotfix, one could just copy/rename the files in python3.9/site-packages/adminsortable2/templates/adminsortable2/edit_inline/
With the new version 4.2 of Django, some templates (in my case: stacked-django-4.2.html but this should also apply to tabular-django-4.2.html) are missing. The templates for 4.1 can be used and should be included in a newer version of the plugin. As a hotfix, one could just copy/rename the files in python3.9/site-packages/adminsortable2/templates/adminsortable2/edit_inline/