Currently Crowd do not support OAuth authentication yet. However there is already an improvement reqeust being raised in here: https://jira.atlassian.com/browse/CWD-2325
Please feel free to vote on it to increase its popularity and add yourself as watcher in order to receive any latest updates from the developer and feedback from other user that is facing the same issue.
If you were upgrading the legacy app to our new one, you might have run into the error below while trying to authenticate. We're still investigating the cause of this but here's a workaround...
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