location / {
  proxy_pass http://komga-upstream;

  proxy_set_header Host $host;
  proxy_set_header X-Real-IP $remote_addr;
  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
  proxy_set_header X-Scheme $scheme;
  proxy_set_header X-Forwarded-Proto $scheme;
  proxy_read_timeout 90s;
  proxy_buffer_size 128k;
  proxy_buffers 4 256k;
  proxy_busy_buffers_size 256k;
}

location ~* "^/kobo/(.+)/v1/initialization$" {
  proxy_pass http://komga-upstream;

  proxy_set_header Host $host;
  proxy_set_header X-Real-IP $remote_addr;
  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
  proxy_set_header X-Scheme $scheme;
  proxy_set_header X-Forwarded-Proto $scheme;
  proxy_read_timeout 90s;
  proxy_buffer_size 128k;
  proxy_buffers 4 256k;
  proxy_busy_buffers_size 256k;

  sub_filter https://www.instapaper.com "https://sub.example.com/instapaper-proxy/instapaper";
  sub_filter_types application/json;
}