OR_HOSTNAME=<own IP> blank manager screen 403 forbidden

I tried running openremote on my local machine which works fine. Now I want to be able to access the ui on my IP address, lets say 1.2.3.4. On a windows pc running Docker Desktop I checked out the custom project github (GitHub - openremote/custom-project: Template repo for creating an OpenRemote custom project) and followed the guide (Custom deployment | OpenRemote Documentation). I have had this working on localhost, so now I am running the following command inside the custom-project repo:
cmd /C “set OR_HOSTNAME=1.2.3.4 && docker compose up”

I can now reach the log in screen on 1.2.3.4 and use the same username and password as before, but after log in I get a blank screen. In the console I get a 403 forbidden from POST request to https://1.2.3.4/api/master/console/register