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VirtualBox: Extension packs

Extension packs for Oracle VM VirtualBox can be downloaded from https://www.virtualbox.org/wiki/Downloads.
Although VirtualBox is free and open source software, the extension pack(s) is proprietary software.
On the command line, an extension pack can be installed with 
VBoxManage.exe extpack install p:\ath\to\extension-pack.vbox-extpack

See also

Installed extension packs are shown with 
VBoxManage list extpacks

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