I wasn’t criticizing the guide — just pointing out real OAuth2 pitfalls that still affect users.

The spec itself made mistakes:

• Silent account hijack via “Connect this provider.”

• Redirect leaks of code (via Referrer) or access_token (via #hash).

• CSRF because state was optional and often ignored.

The point is: these aren’t obscure edge cases, they’re structural issues baked into the protocol.