Trying to validate Custom Fields in the Add and Edit Client forms. If validation fails, the changes should NOT be committed to the WHMCS db.
I've been trying to utilise the ClientDetailsValidation hook. However, the documentation for it is wrong. It is not triggered before ClientAdd, it seems to only be triggered before ClientEdit. What's more, even if ClientDetailsValidation returns an error, the entered details are still committed to the WHMCS db. What is up with this? Is this a bug?
Alternatively, is there anyway of disabling/hiding the custom field in the Client Edit or Client Add forms?