How to update to Libreoffice 6.4 from 6.3 in ubuntu 18.4. Update otion in Tools>option>Libreoffice doesnot show Update?
Option 1. Just wait. Most probably, the maintainers have not prepared updates yet.
Option 2. Or download deb packages from the official site and install. If, however, you don’t understand how to do what I have written here, stick to the Option 1.