OAuth has something called the “Resource Owner Password Credential (ROPC) Grant1.” In fact, some banks use it, and I occasionally receive questions from developers who have seen this, such as, “We can use this too, right?”
This YouTube video uses animation to explain what ROPC is and then explains the circumstances in which ROPC may be used. The audio is in English, but Japanese subtitles are also provided, so I hope you will watch it with Japanese subtitles turned on.
Footnotes
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