Preserve user info / login data between sessions

Hi there

Currently I have a few thousand regular users on my app and I offer them SSO through Discord (which works quite well). The problem is I am struggling to find a way to preserve that login detail between sessions (or when the user refreshes the app). Is there any way for me to preserve the token from between sessions client-side and allow people to pick back up where they left off without needing to authenticate every single time?

Discord and general sso is not a hard stop on this - happy to look at any and all methods of preserving user info from session to session.