Discourse で Google サインアップを設定するのに助けが必要です

[MarcP]

Seems you are describing step 12 here. The app needs to be verified.

@system

1. To get it fully working, you now have to change the status to In production . This means filling in a few more things, and submitting it for verification. They asked me to upload a video to YouTube explaining the privacy policy to users. For details see this:

• OAuth API verification FAQs - Google Cloud Platform Console Help