Nothing a local links webpage can't do Puntuado con 2 de 5 estrellas

Unless I am missing something, you can simply put all these links on a local page, bookmark it and you don't need one more addon, button or menu item. Also, some configuration would be necessary (eg user id/password for auto-logon and choice of national ebay version like

Esta valoración es de una versión anterior del complemento (0.3).