Add Libreoffice offical respotory:
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sudo add-apt-repository ppa:libreoffice/ppa
sudo apt-get update
sudo apt install libreoffice libreoffice-kf5 hunspell-en-ca


From: https://launchpad.net/~libreoffice/+archive/ubuntu/ppa

Origoal Date in Vivaldi: 18 August 2018 @ 17:44 through March 9th 2023


Update September 22nd 2025:
libreoffice-kde has been replaced by libreoffice-kf5 (for both KDE 5 & KDE 6)