The Tip Show How-to Add the Nextcloud PPA Apt Repository for Ubuntu/Mint GNU/Linux Desktops.
Nextcloud gives organizations fine-grained Control over Data Access, facilitates File Sync and Sharing across Devices, enables collaboration within and across organizational boundaries and lets users communicate through secure audio and video Conferencing.
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Open a Command Line Terminal Session
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Enabling the Nextcloud Apt PPA
sudo su -c "apt-add-repository -y ppa:nextcloud-devs/client"
If Got “User is Not in Sudoers file” then Look: Solution
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Refreshing Apt Repositories
sudo apt update