Ok, I’ve figured it out.
Here is what I found in Nginx logs:
2023/09/21 23:35:10 [error] 2659942#2659942: *522258 upstream sent too big header while reading response header from upstream, client: 192.168.168.1, server: my.hostname, request: "POST /callback HTTP/2.0", upstream: "https://192.168.168.135:7176/callback", host: "my.hostname", referrer: "https://my-domain.us.auth0.com/"
So it works fine after adding this buffer config to Nginx:
server {
proxy_busy_buffers_size 512k;
proxy_buffers 4 512k;
proxy_buffer_size 256k;
# rest of the nginx config below #
}
Don’t forget to bump your Nginx memory 