Switching on Enterprise Edge breaks Azure AD B2C auth

**Describe the bug**

When an existing Static Web App using Azure AD B2C for its auth provider and a custom domain has Enterprise Edge switched on, it attempts to redirect the user to the wrong address - wonderful-pebble-blah.origin.staticwebapps etc. This flags an error with Azure AD B2C for not being in the allowed list or redirect URI's - when added to that list the redirect simply sits there and does nothing.

**To Reproduce**
Steps to reproduce the behavior:
1. Set up a static web app with Custom Domain and Azure AD B2C as a custom auth provider
2. Click on Enterprise Edge
3. Attempt to login using the /login route
4. Shows error about redirect URI not being allowed

**Expected behavior**
Azure AD B2C login to continue to work using the custom domain registered with the static web app when Enterprise Edge is switched on
**Screenshots**

**Device info (if applicable):**
Windows
Chrome
Latest

**Additional context**
I switched off the Enterprise Edge feature and the login worked again after ten minutes. It may well also be that this isn't a bug as such, but that I just need to add some more DNS records or something. In which case I guess its more of a documentation thing!