Event registration by an administrator sends confirmation email regardless of confirmation setting

When recording an event registration through the back-end (i.e. as an administrator) it is possible to untick the checkbox against the setting labelled as "Send Confirmation" or for a paid event "Send Confirmation and Receipt". The expected behaviour is that when this checkbox is unchecked then no email will be sent. In practice this setting appears to be ignored and the email notification is sent regardless.

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