Login emails pointing to localhost? Fix your auth redirect URLs

Signup works in preview, but on your live domain the confirmation or password-reset email sends people to localhost:3000, an old preview URL, or an error page. The usual cause: your auth provider still has the old address on file.

In Supabase, open Authentication, then URL Configuration:

• Set Site URL to your live domain, with https.
• Add every address you actually use (custom domain, the www version, your preview URL) to Redirect URLs.

Then sign up on the live site with a fresh email and click the link yourself. A test that passed in preview doesn't prove the live flow works.

Run the free 30-second check to see what your live app shows real visitors.