My Firebase Website Only Allows One User Logged In At All Times, Why?

SITUATION: If I log in from one device and open the website on any other device (my phone, my friend's laptop, my neighbour's pc), the website shows me as logged in on all those de

Solution 1:

If you're using the node.js admin SDK, you are effectively in a single-user situation, and your server is the single user. Typically, that single user is a privileged service account, but it appears you're using it to log in individual users simultaneously. That's not a supported use case for the admin SDK.

If you want per-user login for your web site, you'll have to authenticate in the browser itself using the web SDK. The web SDK communicates directly with Firebase services, securely, on behalf of the user that's signed in.