Chrome – How to know if your browser is connected to the Ipv4 or Ipv6 address of a website

Well, there's IPV6 tunnels and proxies. You're talking about a tunnel in this case I believe.

If you want to access IPv6 resources as a client, I believe installing Teredo should do the trick, somewhat slowly - netsh interface ipv6 install installs IPV6 support and netsh interface ipv6 set teredo client installs teredo

Setting up IPV6 tunnels is a pain unless its a single computer connected directly to the net, or your router can connect to a tunnel broker.

The only options thats worked on my specific setup is the gogo6 client with the udpv6 option, and its worked perfectly behind a lan with no other configuration for me. Gogo went defunct and their webpage has a domain squatter so it won't work any more.

As for tunnel broker - I notice you've tried this but without knowing the specific errors and messages its hard to say what is going on.

If its 'simply' to access ipv6 websites there might be 6 to 4 proxies - sixxs had a web proxy available, but they shut down services in 2017

Another avenue of Attack--

I've had to install Chrome on our office machines to access an EHR that works best on Chrome, but we still need to use Firefox and IE for other websites.

In your case...if Chrome is ALREADY installed and behaving as the Default Browser...

1. FULLY UNINSTALL IT
2. Shutdown and Restart Windows
3. Go to the Browser of your choice that you want to be Default and RESET it as Default in whichever Settings is needs.
4. If you need to Go to the Chrome Website to Download it afresh WATCH for the CHECKBOX that is ALREADY CHECKED TO MAKE CHROME THE DEFAULT BROWSER...UNCHECK IT!! (Better Still-- Hunt/Google for the Off-line Install MSI-- Chrome will Update itself automatically afterwards)
5. Now INSTALL Chrome again. Except THIS time...when Chrome finishes installing and opens up to the Initial Setup/Login Tabs, turn it off via the hamburger Menu.
6. Now Activate/Open Chrome again.
7. When Chrome Opens for the SECOND time, you will see a Dropdown bar at the top where Chrome ASKS you if you want it to be the DEFAULT Browser. Select DO NOT ASK AGAIN

As you now know--Once you Give Chrome Default Status..it doesn't let go of it. The trick is to remember to NEVER give it Default Status from the INITIAL INSTALL.

Now Chrome will remain 'hopefully' subservient to IE or Firefox thereafter.