Bitwarden + NGROK + client/browser extention doesn't work

Hi everyone.
I’ve recently self-hosted Bitwarden. As expected, I needed an SSL certificate to register successfully. Since I don’t have a domain and don’t plan to purchase one, For my personal needs VPN is the only way which I connect my network from remote if needed.
By googling I found a solution using ngrok which sound very prommising.
After registering, I got a ‘private link’ that simulates having a certificate. It’s something like :

https://my_personal_number.ngrok-free.app/

It works perfectly and everything functions as it should. By that I mean : I can log in to my Bitwarden web page, I’m able to create a new org, add new passwords, etc. I’m really happy about it.

However, I wanted to take it a step further and installed the Bitwarden client (from Flatpak) on Ubuntu 22.04. I also added the browser extension to Brave. Unfortunately, the client and the browser extension don’t accept the link generated by ngrok. I can’t log in this way. So far, I’ve created a network for ngrok and Bitwarden, and set up the containers for both like bellow.

  docker network create ngrok
  
  docker run  --detach \
  -e NGROK_AUTHTOKEN=$NGROK_AUTH_TOKEN \
  --network ngrok \
  --name ngrok \
   -p 3333:4040 \
  ngrok/ngrok:alpine \
  http bitwarden:80 --region eu

    docker run -d --name bitwarden \
     --network ngrok \
  -v /myDir/Bitwarden:/data \
  -v /myDir/Bitwarden/ssl:/ssl \
  bitwardenrs/server:latest

Can anybody help me out with that issue, please?

I do realize that creating a volume for ssl isn’t neccesary (it was time when I was tinkering with self signed cert…).