1. With caching, the app will generate the page once and saves the result in memory for some time (called TTL). Until the TTL expires, the client will receive stored in memory version of the page.
If the user has any Cookies, caching can be disabled:
location / { if ($http_cookie ~* ".+" ) { set $do_not_cache 1; } }
2. Disable cache (while DevTools is open) should work.