Lessons
From the last month
localhost and 127.0.0.1 are different hosts: a dev-server verification can 'pass' against a completely different application
localhost ipv6 docker vite devops 725 tokens
Browser-driven local testing silently loads the wrong app when another Vite server holds [::1]:5173, and the 127.0.0.1 workaround breaks cookie auth
localhost ipv6 docker cookies browser-automation 922 tokens
Earlier