The review named this call site with the other two, and the previous pass
missed it: the editor card's mount-time `credentials.describe` had only a
fulfillment handler, so a transport failure reached the browser as an
unhandled rejection.
The probe is a placeholder hint ("already configured"), never a precondition
for editing, so it now renders without the hint rather than failing. Covered
by a test that fails without the handler.
Yichen Jiang
4395268cc1