We have a Webform that creates a single membership. We've set it to use the 'existing contact' which very helpfully pre-fills the webform with the existing user's details - or with the details corresponding to the contact's checksum from a CiviMail. This is all brilliant so far!
However, when the page loads it also shows all the contact's existing memberships. And it shows them in the page's system 'messages' block.
In our use case we don't want to see existing memberships. And even if we did we'd want to see them in a webform component that we can control the behaviour of. When they appear in the system messages block it looks like an extra communication to the user and is rather confusing.
So, is it possible to prevent them from loading at all? Or at least have them load as a component of the webform rather than displaying in the messages block?
We are on Drupal 7.58, Civi 5.0.0