[Bug] When using a third-party IdP the three "reserved" scopes are fixed and cannot be omitted

[lgiuliani80]

Library version used

4.66.2

.NET version

.NET Framework 4.8 (but does not depend on the version of .NET)

Scenario

PublicClient - desktop app

Is this a new or an existing app?

This is a new app or experiment

Issue description and reproduction steps

"openid profile offline_access" are relevand and "mandatory" only if the target IdP is a Microsoft IdP (Entra, ADFS, B2C). Other IdP(s) even actually reject some of those scopes (especially when passed to the token endpoint).
The "reserved" scopes should be passed alongside the user provided ONLY if the target IdP is Microsoft one. For third party identity providers only user provided scopes should be considered.

Relevant code snippets

Expected behavior

No response

Identity provider

Other

Regression

No response

Solution and workarounds

No response