Thank you very much for your interest. I have checked, comparing the files of my installation and the work of Black-Eagle at GitHub - the-black-eagle/lcdproc: Client/server suite for controlling a wide variety of LCD devices and https://github.com/the-black-eagle/script.xbmc .lcdproc that this, in its day added support for the extra icons of the VFD Futaba TOSD-5711BB. However, such support is not included in Libreelec. I have contacted him, through the Kodi forum. If someone is interested in the subject, this is the url Futaba TOSD-5711BB LED display driver
It is an old hardware and, apparently, little used today.