Blank page when redirect to <domain>.auth0.com/u/login

[HLR]

Likely the same problem reported here:

Using sample PHP code on iOS 12 -- Auth0 login page hangs

Hello All, I have Auth0 working great with my PHP application with Google, Facebook, Twitter, Amazon and Apple. It all works really well, 50% of the time. But 50% of the time when I call the “$auth0->login();” call in my PHP code, it correctly opens up to the .auth0.com login page for my app, the page in Safari or Chrome on iOS 12 it only shows the top header bar which is blank, but never actually loads the login options. See the first image below. If I do a simple page refresh, the login p…

and here:

The login window in a WKWebView on macOS is sometimes broken

I am showing the login window in a native desktop app on macOS Catalina in a WKWebView with an URL in the following form: https://XXX.eu.auth0.com/authorize?response_type=code&code_challenge=YYYY&code_challenge_method=S256&client_id=ZZZ&redirect_uri=XXX&audience=YYY&state=ZZZ&scope=openid+email+profile Sometimes the login screen appears with only a pink square a the top: [LoginBroken] When I resize the window, or attach the Safari developer debugger the webview resizes and looks ok: [Logi…