Issue Description:

Customers experience authentication redirect issues when using Cloudflare as a reverse proxy with Power Pages and Entra External ID.

Even with correct custom domain and redirect URI configuration, Power Pages may still generate redirect URLs using the default *.powerappsportals.com domain instead of the custom domain, causing mismatches and authentication failures

Current Limitation:

Power Pages does not support third-party reverse proxies like Cloudflare as a full front-end layer.

This can result in inconsistent redirect handling and authentication failures, while also preventing customers from integrating Power Pages into their centralized security, DNS, and monitoring systems.

Expected Result:

Customers expect:

• Support for Cloudflare as a reverse proxy for Power Pages
• Correct redirect URLs aligned with custom domains
• Reliable authentication with Entra External ID
• Ability to integrate with centralized security and monitoring frameworks