iFrame events not coming through correctly

Description

Using an embedded iFrame of RocketChat on my website, previously I was using detection of the startup iFrame event to run a login script. However, now it seems unable to get the startup event through, but still RocketChat is sending through the Custom_Script_Logged_Out event.
Does anyone know why I might not be getting the startup event anymore? As per RocketChat’s docs, it’s simply an event fired when the iFrame initialises.

I was on Rocket.Chat version 7.13.2 but have since upgraded to 8.4.0 and also done the necessary changes to MongoDB moving it away from 6/7 on bitnami to the official image for 8.2.7. This doesn’t appear to have made any change for the above issue.

Many thanks in advance for any help!

Server Setup Information

  • Version of Rocket.Chat Server: 8.4.0
  • Operating System: Ubuntu 22.04.3 LTS
  • Deployment Method: Docker
  • Number of Running Instances: 1
  • DB Replicaset Oplog:
  • NodeJS Version: 22.16.0 - x64
  • MongoDB Version: 8.2.7
  • Proxy: Traefik v3.4
  • Firewalls involved: ufw (Uncomplicated Firewall) with ports 80 & 443 manually opened.

To add, my settings should be working correctly for iFrame events: