When connecting to HA URL via https the login screen is blank (but is working using the IP address)

**iOS device model, version and app version**
Model Name: iPhone 12
Software Version: 16.7
App version: 2023.4 (2023.460)

**Home Assistant Core Version**
2023.10.1

**Describe the bug**
When starting the Companion App autodiscover identifies my homeassistant URL. Connecting to that URL issues an error message about the untrusted certificate. Trusting the certificate brings you to an empty login page.

Adding a server manually and using the IP address of the same server I get the login page, after the certificate message of course.

**To Reproduce**
Just connect to the HTTPS URL while HA is configured to use a certificate from private PKI infrastructure.

**Expected behavior**
the login screen is shown regardless if I use the IP address or the URL of the HA host.

**Screenshots**

**Additional context**
I am running my own DNS server which is authoritative for my "fire.fly" domain and resolves to the IP address of my HA VM.

The certificate used is a SAN certificate configured as follows:
CN: homeasistant.fire.fly
SAN-Names:
DNS1: homeasistant.fire.fly
DNS2: homeassistant
IP1:

It is signed by my personal CA where I am not able to install the Root-CA-Cert on the iOS device! Hence there always will be an error message about the trust chain. On my windows clients the trusted root is installed, and everything works perfect in the browsers.