Prevent redirect page flashing

Getting advice
1

When going to the front-end URL of a realm, the GUI elements are loaded and then removed again to show the login page. See this screen recording. It’s especially noticable for far away users.

How to prevent that?

We have configured our Nginx to redirects visitors on the root page to /realms/<realmname>/account. This ‘account’ page tries to load, but fails.

Is have not been able to find another URL that just shows the login page. Is there one? But even so, when people go to their account page, this page flashing should not happen.

Keycloak version 26.2.5, proxied by Nginx. Note that we only proxy these locations (as per the docs):

location / {
    return 301 https://login-test.example.com/realms/example-realm/account;
}
location /js/ {
  include keycloak-proxy.inc;
}
location /realms/ {
  include keycloak-proxy.inc;
}
location /resources/ {
  include keycloak-proxy.inc;
}
location /robots.txt {
  include keycloak-proxy.inc;
}