@ mason, loldier, Magic Banana Thank you very much.The data and questions with which you have contributed, have encouraged me to deepen my studies on .html editing. Considering the set of options I already knew and the new ones that you have suggested, I think, that for the time being, the best substitutes for my Seamonkey dependent Compose is a combination of LibreOffice Writter and Abrowser's Web developer tools.
Thank you all for trying to help
