How do I change the default GL Account (not the Cash Account) on the Payments window?

How do I change the default GL Account (not the Cash Account) on a Payments (Pay Bills) window?

When Customer ID is selected:

The default value will be the Accounts Receivable account last assigned for use on the sales invoicing screen. Changing this default selected account requires changing the A/R account used in Sales Invoicing.

When Vendor ID is selected:

Update the Expense Account on the vendor record. See DocLink: How do I create a new vendor?.

DocLink: General ledger (GL) account field is missing on task windows