this took me way to long to find the right answer on Google (ironically).
When you access ACM having it present it's default self-signed certificate you can run into problems on macOS and Chrome. Even if you have the certificate installed in your keychain and other browsers (Safari, Firefox) have no problems at all, Chrome might give you something like this:
There is no way to bypass that page, no way to overwrite and proceed anyways. Or so it seems.
What you have to do is on that page type in
I am not making this up. After you typed in that phrase the browser will automatically proceed to the login page.