@ConnyDuck it's missing from the API, see here: https://github.com/tootsuite/mastodon/blob/master/app/controllers/api/v1/accounts/credentials_controller.rb (line 23)
and compare to the main ProfilesController https://github.com/tootsuite/mastodon/blob/649a20ab46eadf9ae3bfc30782ae62379383bd72/app/controllers/settings/profiles_controller.rb (line 28)
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