@mingu I've got good news for you - Libreoffice is available under either the Lesser GNU General Public License version 3 (or at your option) any later version, or the Mozilla Public License version 2, neither of which say "open" in them - which means it doesn't have the proprietary shallowness of "open source", rather it is free software - or alternately libre software (it's even in the name).

https://www.libreoffice.org/download/license/