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I see this error too when third party cookies are blocked. I noticed an issue has already been filed for the underlying MSAL library: https://github.com/AzureAD/microsoft-authentication-library-for-js/issues/1880

Thanks @heisters, I hit this too and you saved me some debugging time.

On a second search through the issue list, I see this is highly related to (but not quite the same as) existing issue #1183.