Augment PKCE autodiscovery

[alnr]

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• I could not find a solution in the existing issues, docs, nor discussions.
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Ory Network Project

No response

Describe your problem

Some providers (Microsoft, Salesforce, maybe more) don't advertise PKCE but do support it.

Describe your ideal solution

We should earmark those providers as supporting PKCE, and when config option pkce==auto in the Kratos OIDC provider configuration, skip autodiscovery and perform PKCE.

The Salesforce docs need updating to reflect Kratos now supports PKCE.

Workarounds or alternatives

Don't have automatic PKCE for some providers and let users configure pkce==force if they want it.

Version

1.2

Additional Context

No response