OK, so I managed to add oauth-sign as a dependency so that problem is solved.
But I’m running into a worse problem. Previously user.identities contained the access_token and access_token_secret of the social provider. But now event.user.identities only contains connection, isSocial, provider, userId and user_id. userId and user_id are the same and neither contain the twitter access token and access token secret. How do you access the social identity provider access token in an action? I’ve tried to search the documentation and couldn’t find anything.