Withings integration loop

Gday,

Im trying to set up the new withings integration. I updated my configuration with the keys like this:

withings:
  base_url: https://nottelling.ui.nabu.casa
  client_id: yyyy
  client_secret: xxxx
  profiles:
    - Chris

I had to use the remote UI as the withings app redirect URI needs to match the base URL (you cant simply enter “anything” in there like the instruction suggest) however it wont accept anything not running on port 80 or 443!

On the next step I select my profile and authorise the app and then a new windows is opened with the same withings profile selection. If I re-do the authorisation, the redirect fails with a 500 error.

I am not running dyndns as I have a fixed IP.

Any ideas how I can get this running?