To delete a customer, get their name into the summary list view, click the checkbox to the left, and click “Forget”. This does two things, neither of which can be undone, so use this feature carefully:
The customer’s name and contact info are permanently removed from the database.
Any purchases, donations, etc. made by the customer are transferred to the “Anonymous Customer”, a special fictional customer named “ANONYMOUS”, so that the books still balance. If Alice Johnson donated $1,000 and then you “Forget” her account, the $1,000 donation will now be “credited” to the anonymous customer instead. This cannot be undone. In the future there will be a way to make a customer “inactive” (so they don’t show up in searches and reports) without using Forget.