[Lizard]

It looks like a Support Ninja already replied to your email, but for the sake of anyone else encountering this...

Yes, we're aware of the issue and are looking into it. (Initial diagnosis suggests it's going to be a fair bit of work, unfortunately...)

Since the issue seems to be specific to the inbox, one (admittedly clumsy) workaround would be to create a Single Action List to use as your inbox instead.