Is there any way to log into SN using the Nostr login option without using an extension? I understand the importance of what nostr extensions offer, but there should be a better option.

Specifically on mobile, I'm unable to log into SN unless I use an extension.

Does anyone know of a self-hosted gateway solution of sorts that bridges access to a Nostr key like the extension does, but not just locally? There would obviously need to be site-side implementation to allow for this but would be far more accessible than simply not being able to login.