Dear @Lubos
It turns out that I ran into a problem with the ledger account that is generated for certain withholding taxes on purchase invoices.
When I activate the “Withholding tax” box, the “Withholding tax payable” account is created. But that account itself is unchangeable. In this case I want to use another control account to accumulate the tax withholdings, that is, as a user I want to have the possibility to choose the control account on which I prefer to work.
It doesn’t even allow me to place the ledger account in a group.