When you start typing an address in the To: / CC: / BCC: fields, a popup will appear that offers matching addresses that have been used recently and matching addresses from your address book; if you do not like the automatic popup you can disable it by clicking with the & RMB; on the field and choosing a different completion mode.
Ao comezar a escribir un enderezo nos campos Para: / CC: / BCC: aparece un texto que ofrece enderezos que coinciden cos que se empregaron recentemente e cos que hai no caderno de enderezos; se non lle gusta ese texto que aparece poemo desactivar premendo co & RMB; no campo e escollendo un modo de completado diferente.